Originally Posted by bearisgray

Using a needle when it should be changed - it was making noise when it was going through the fabric - put a new needle in - much quieter sewing!

Also using the wrong needle for the fabric being sewn.

Not realizing that the knives ( blades) on a serger do eventually get dull and mangling some fabric before realizing that a dull knife was part of the problem.

Using weak thread. Thread can look good and be a "good" brand and still have weakened. Check it before using it.

Trying to use bobbins that are iffy.

Using appliances with bad wiring.

Using iffy fabric.

Using an inadequate extension cord.

Saving bent or rusty pins.

More?