Why Factory Samples Get Rejected: 10 Tech Pack Mistakes That Cost Brands a Sample Round

A tech pack for manufacturer partners has one job: to let a factory make your product exactly as you imagined it, without guessing. When a sample arrives wrong, the cause is usually a missing tolerance, a vague fabric note or an outdated file, not poor sewing. Ten mistakes cause most of the rejected sample rounds, grouped across measurements, materials, construction and artwork, and communication. Genpire generates factory-ready tech packs from a sketch or a short prompt, so these fields are filled in before you send anything.

A tech pack for manufacturer partners has one job: to let a factory make your product exactly as you imagined it, without guessing. When a sample arrives wrong, most brands blame the factory. Look closer and the cause is usually on the page. A missing tolerance, a vague fabric note or an outdated file sent by mistake.

Every rejected sample means another round of fees, courier costs and waiting, and it pushes your launch date back. The ten mistakes below are the ones that trigger those extra rounds most often, grouped by where they hide.

Measurement Mistakes

1. No tolerances

A chest measurement of 52 cm means nothing on its own. Is 53 acceptable? Is 51? Without a plus or minus value for each point, the factory decides for you, and their idea of "close enough" may not match yours.

2. Unclear points of measure

"Body length" can be taken from the high point shoulder, the center back neck or the side seam. If you do not define the start and end point, two people can measure the same garment and get different numbers.

3. Missing or illogical grading

Many brands perfect the sample size and forget the rest. If grade rules are missing, or jumps between sizes are uneven, the fit falls apart at the ends of your range.

4. Not stating pre-wash or post-wash

Garment-dyed or washed products shrink. If your chart does not say whether measurements apply before or after washing, a perfectly sewn sample can still come back a size too small.

Material Mistakes

5. Vague fabric descriptions

"Soft cotton jersey" is a mood, not a spec. List composition, weight in gsm, construction and finish. If you already have an approved fabric, include the supplier reference.

6. An incomplete bill of materials

Thread color, interlining, elastic width, care labels, hangtags. Small items left off the list either get substituted or delay the sample while the factory waits for an answer.

7. Color by description only

"Forest green" looks different on every screen. Give a recognized color standard reference or a physical swatch, and ask for lab dips before bulk fabric is dyed.

Construction and Artwork Mistakes

8. Missing stitch and seam details

Stitch type, stitches per inch and seam finish shape both durability and appearance. Leave them out and the factory will use its default, which may look cheaper than you intended.

9. Artwork without placement measurements

A print shown "on the chest" can land anywhere. Specify the artwork size and measure its position from a fixed point, such as 7 cm below the high point shoulder and centered.

Communication Mistakes

10. Version confusion

Comments spread across emails, chats and marked-up PDFs lead to a factory sewing from the wrong version. Keep every change inside the document, with a version number and date on each page.

How Do You Check a Tech Pack for Manufacturer Readiness?

Before you send anything, run through five quick questions:

Does every measurement have a defined point and a tolerance?
Is every material and trim listed with a specific reference?
Are colors tied to a standard or a physical swatch?
Are construction and artwork placements measured, not just described?
Is this the latest version, clearly labeled?

If any answer is no, fix it now. It is far cheaper than fixing it after a sample flies back. For a full breakdown of every section a factory expects, this guide to building a tech pack for manufacturer teams to work from is a useful reference.

FAQ

How many sample rounds are normal?

It depends on product complexity and how established your specs are. Simple repeat styles may be approved quickly, while new fits often need more than one round.

Should I send a reference garment with my tech pack?

If you have a garment with the exact fit or finish you want, yes. Note which details to copy and which to ignore.

What is the most common cause of a rejected sample?

Most rejections trace back to gaps in the tech pack itself, not poor sewing. Missing tolerances, vague fabric descriptions and unclear points of measure are the most frequent causes.

Get It Right on Paper First

Most sample rejections are not caused by poor sewing. They come from gaps in the document the factory was given. Define every measurement, name every material, measure every placement and keep one clean version, and your first sample has a real chance of being your last. If building that level of detail by hand is slowing you down, Genpire generates factory-ready tech packs from a sketch or a short prompt, so you can spend your time reviewing instead of formatting.

Try it on your next style and send the factory a document that answers its questions before they are asked.