It can't - assuming they managed to print the angles in the right order! As long as the needle is magnetized it will work, cheap button compasses have weak needles that are easily demagnetized.

You can have compasses that are faster to settle, clearer to read and work more reliably if they aren't held exactly flat.

If you live on the east or west coast get one with declination adjust or just draw a new north line with a sharpie. If you line down the middle, or in the UK just buy any baseplate compass.

One degree off means you are only going to be out about 25yards in a mile, and there aren't many places you are marching purely on a compass bearing further than that without any landmarks.