Pull compensation.

Every needle penetration drags the cloth inward toward the stitch line, so a satin column sewn at its drawn width comes out narrower than drawn and gaps open where it should meet the shape beside it. Pull compensation is the width the digitizer adds back before the file ever reaches the machine, either by overlapping objects by hand or as an overstitch allowance in millimetres. The value belongs to the fabric, not to the artwork: Wilcom's guideline table asks 0.20 mm on drill and cotton, 0.35 mm on a T-shirt, 0.40 mm on fleece, and 0.2 to 0.3 mm for lettering (Wilcom EmbroideryStudio help). Hooping and column width move it further, which is why a file that ran clean on woven jackets shows garment color between the letters on the polo order. Overdoing it is a defect of its own: fat letters, filled-in counters, a logo that no longer matches the brand sheet, and nobody notices until the customer holds the shirt next to their guidelines.