Good feedback creates better products.
Sample evaluation is one of the most important stages in product development.
It is also one of the stages where projects can lose the most time.
The reason is simple:
Product feedback is often too vague.
Comments such as:
“It feels quite good.”
or
“Can you make it a little more premium?”
or
“I think the previous sample was better.”
do not give a development team enough information to act efficiently.
A good sample-evaluation process turns subjective impressions into structured development feedback.
The purpose of a sample
A development sample is not simply there to impress the customer.
Its purpose is to answer specific questions.
For example:
Is the cleaning power strong enough?
Is the viscosity appropriate?
Is wipe-off acceptable?
Is the fragrance direction correct?
Is the product close to the benchmark?
Is the application behaviour suitable?
Should a specific characteristic be increased or reduced?
Each sample should move the project closer to the approved product.
Know what version you are testing
Every development sample should have a clear identity.
For example:
PL-0248-V01
PL-0248-V02
PL-0248-V03
The version should also state what changed.
For example:
V02
Changes from V01:
increased lubricity
lower viscosity
adjusted fragrance level
V03
Changes from V02:
improved rinse behaviour
reduced foam
fragrance unchanged
This is important because otherwise feedback becomes unreliable very quickly.
Never test unidentified samples
Avoid descriptions such as:
“the blue one”
“the sample from last week”
“the second bottle”
“the stronger-smelling version”
Once several people and several development rounds are involved, this becomes almost impossible to manage.
Every sample should be traceable.
Read the testing instructions first
A product can perform badly simply because it is tested incorrectly.
Before evaluating, understand:
application method
dilution
dwell time
surface condition
required quantity
removal method
curing time
temperature restrictions
recommended tools
A product designed for 1:20 dilution should not be judged at 1:5.
A coating should not be judged before the required curing period.
A wheel cleaner should not be allowed to dry if that is outside the intended use.
Testing conditions matter.
Test against the brief
The most important reference is not your mood on the day.
It is the agreed development brief.
The question should be:
Does this sample meet the target we defined?
Not:
Do I personally like it?
These are sometimes very different questions.
Separate objective and subjective feedback
Both are useful.
But they should not be mixed.
Objective feedback
Examples:
product streaked at 25°C
dilution 1:50 was insufficient
trigger created excessive foam
coating required two towels for removal
drying time was approximately 4 minutes
residue remained after rinsing
These observations are highly actionable.
Subjective feedback
Examples:
fragrance feels too sweet
finish feels more premium
foam looks better
slickness feels excellent
colour feels too aggressive
These are also useful.
But they should be labelled as preference rather than technical fact.
Evaluate one characteristic at a time
It is easy to form a general opinion too quickly.
Instead, separate the product into individual attributes.
Depending on the category, these may include:
application
cleaning power
gloss
slickness
hydrophobicity
foam
lubricity
fragrance
viscosity
wipe-off
residue
finish
drying behaviour
durability
material compatibility
overall user experience
This creates useful information.
Use a consistent rating system
A simple five-point scale works well.
1 — Unacceptable
Does not meet the requirement.
2 — Below target
Significant improvement required.
3 — Acceptable
Usable, but not yet where we want it.
4 — Good
Meets the target well.
5 — Excellent
At or above the desired target.
The important part is consistency.
Ratings alone are not enough
A score should be accompanied by a short explanation.
Instead of:
Wipe-off: 3/5
write:
Wipe-off: 3/5 — good at room temperature, but begins to streak on a warm panel.
Instead of:
Fragrance: 2/5
write:
Fragrance: 2/5 — direction is acceptable, but intensity is too low during application.
That makes the rating useful.
Always answer three questions
For every sample, feedback should include:
What do you like?
This tells R&D what should remain unchanged.
What should improve?
This defines the next development step.
What must not change?
This is often overlooked.
If a sample has excellent application but weak fragrance, the next version should not accidentally lose the good application behaviour.
Compare with the previous version
When testing V03 after V02, ask:
Did the intended change work?
Did anything else improve?
Did anything else get worse?
This is important because formulation changes can have side effects.
For example:
Increasing fragrance may improve sensory appeal but reduce clarity.
Increasing viscosity may improve cling but worsen spray behaviour.
A development version should be assessed as a whole.
Compare with the benchmark
Where a benchmark exists, test side-by-side where practical.
For example:
CLEANING
Sample: 4/5
Benchmark: 4/5
WIPE-OFF
Sample: 5/5
Benchmark: 3/5
FRAGRANCE
Sample: 3/5
Benchmark: 5/5
This gives the developer much clearer direction.
Use the same testing conditions
Side-by-side comparison only makes sense if conditions are similar.
Try to keep consistent:
surface
temperature
dilution
product quantity
applicator
microfiber
machine
dwell time
water quality
Otherwise, the test may reflect the environment more than the chemistry.
Test more than once
One application can be misleading.
Where appropriate, repeat the test.
Especially when evaluating:
coatings
polishes
wheel cleaners
shampoos
interior products
A sample that performs well once but inconsistently is not necessarily ready.
Test in realistic conditions
Laboratory-perfect conditions are useful.
Real-world conditions are also important.
Consider testing:
different temperatures
different vehicle surfaces
clean and contaminated surfaces
coated and uncoated surfaces
professional and consumer users
different application quantities
The exact approach depends on the product.
Do not change the test method halfway through
If V01 was tested one way and V02 another, the comparison becomes weaker.
When possible, maintain a consistent evaluation protocol throughout development.
Sample quantity matters
Using too much product can make a sample appear:
harder to wipe
streakier
foamier
more expensive to use
Using too little can make it appear:
weak
dry
difficult to spread
less effective
Use the intended application quantity.
User experience is part of performance
A product may technically work but still feel poor to use.
Evaluate:
how easily it spreads
how it sprays
how it smells
how quickly it works
how easily it removes
how much product is required
whether the process feels intuitive
A commercially successful formulation usually needs both performance and usability.
Fragrance evaluation
Fragrance should be evaluated at several points.
In the container
How does it smell initially?
During application
Is the fragrance pleasant at working concentration?
After application
Does it remain?
Should it remain?
Over time
Does the fragrance remain stable?
A fragrance that smells good from the bottle may behave very differently during use.
Viscosity evaluation
Do not judge viscosity only by appearance.
Ask:
does it spray properly?
does it cling appropriately?
does it pour correctly?
can it be dosed easily?
does it feel premium?
does it create filling concerns?
does it trap air?
The correct viscosity is the one that suits the application.
Foam evaluation
More foam is not automatically better.
Assess:
foam volume
foam density
foam stability
rinse behaviour
lubrication
cleaning performance
Different applications require different foam profiles.
Wipe-off evaluation
For sealants, coatings, detailers and similar products, evaluate:
initial spread
open time
first wipe
final buff
streaking
residue
sensitivity to temperature
sensitivity to application quantity
This can be more useful than simply saying “easy” or “difficult”.
Durability testing
Durability claims require patience.
Do not approve durability based only on initial water behaviour.
Consider:
time
washing
chemical exposure
weather
mileage
maintenance products
surface preparation
A product that looks impressive on day one may not necessarily remain impressive.
Do not overreact to one tester
One person’s preference can be useful.
It should not automatically redefine the product.
For important developments, consider feedback from several relevant users.
For example:
product manager
professional detailer
distributor
internal application specialist
Then consolidate the feedback.
Consolidate feedback before sending it
This is critical in larger organizations.
Do not send:
Person A:
More foam.
Person B:
Less foam.
Person C:
Foam is fine.
R&D cannot develop three contradictory products at once.
The customer should consolidate internal feedback into one agreed direction.
One decision-maker helps
Every project should have one person responsible for final development decisions.
That person does not need to conduct every test.
But they should resolve conflicting internal opinions before feedback is submitted.
This saves enormous time.
Avoid development by committee
If ten people can independently request formulation changes, development can become endless.
A better structure is:
Multiple testers
↓
Consolidated feedback
↓
One approved customer response
↓
R&D action
This keeps development controlled.
Distinguish a problem from a preference
Example:
The product leaves visible residue after application.
This is a technical issue.
Versus:
I personally prefer a sweeter fragrance.
That is a preference.
Both may matter.
But they should not be treated equally.
Avoid changing unrelated characteristics
If V04 solves the main problem, do not automatically reopen every other element of the product.
For example:
Application is now perfect. Could we also completely change the fragrance and colour?
That may create additional validation work.
Changes should have a clear commercial reason.
Know when to stop
Development can continue indefinitely.
There is always something that could theoretically be changed.
At some point, ask:
Does the product meet the brief?
Does it perform at the required level?
Is it commercially appropriate?
Are remaining changes meaningful?
If yes, the right decision may be approval.
Not V17.
Technical approval
When the customer is satisfied that the product meets the agreed target, it should be formally approved.
That creates a clear milestone:
DEVELOPMENT FREEZE
From this point, the formulation moves toward validation and production readiness.
Why Development Freeze matters
After approval, further changes may affect:
stability
packaging compatibility
classification
documentation
manufacturing
cost
timelines
For this reason, technical approval should mean something.
A formulation should not remain permanently open for casual adjustment.
Example Sample Evaluation Sheet
PROJECT
Customer:
Product:
Project ID:
Sample ID:
Version:
Date:
DEVELOPMENT NOTES
What changed from the previous version?
TEST CONDITIONS
Surface:
Temperature:
Dilution:
Application quantity:
Application method:
Other relevant conditions:
EVALUATION
Rate 1–5.
| Attribute | Rating | Notes |
|---|---|---|
| Overall performance | ||
| Application | ||
| Benchmark comparison | ||
| Fragrance | ||
| Appearance | ||
| Residue | ||
| Finish | ||
| Commercial suitability |
Additional product-specific criteria:
WHAT WORKS WELL?
WHAT SHOULD IMPROVE?
WHAT MUST REMAIN UNCHANGED?
BENCHMARK COMPARISON
Better than benchmark:
Equal to benchmark:
Below benchmark:
DECISION
☐ Approved
☐ Approved subject to minor defined change
☐ Another development round required
☐ Not suitable
REQUESTED CHANGES
The Infinitec approach
At Infinitec, sample feedback should create a clear development action.
Each version is identified.
Relevant changes are documented.
The customer evaluates against the agreed brief.
Feedback is consolidated.
The next version addresses specific objectives.
The process continues until technical approval is reached.
The goal is not endless iteration.
It is controlled improvement.
The key principle
Do not ask:
“Do I like this sample?”
Ask:
“Does this sample achieve the target we agreed?”
That single change makes product development far more efficient.
Evaluating a current project?
Use our structured Sample Evaluation Sheet to provide development feedback.
Or start a development project with Infinitec.
Continue reading:
Next: Why Good Lab Samples Can Fail in Production
Practical Tool
Open the working templateRelated Reading
Explore Custom Formulation · Explore Contract Manufacturing