I'm a corner clipper when I have to wash fabrics. (thrift-store/estate sales/etc)
No problems with thread balls after clipping.

Otherwise, when buying new, I don't pre-wash.

I use the wave blade on my rotary cutter. It doesn't eliminate fraying but cuts it way down.

I clipped the corners on the last batch of fabric I washed last week and had almost no fraying. I also wash on the delicate cycle for only 4 minutes. I prewash to get rid of the chemicals and 4 minutes is enough. I also like working with washed fabric rather than unwashed. FQ and small pieces are washed in a mesh bag.

I just make a diagonal snip on each of the corners. Eliminates lots of fraying.

I run mine through my serger before I wash fabric

I always use pinking shears on the cut edges, you still have some raveling but not as much.

I use Fray Check. It does a really good job on cutting down the raveling!!!!

I usually serge both ends, thats my cue "its been washed" ~ and I leave a small amount on there to show the serging, for future reference (I am not always a prewasher ~ but I wet a small piece and check for shrink by watching it.)

I also clip corners and wash on a short gentle cycle.
I also toss in a color catcher with every load...just in case.
One word from experience....any hand dyed fabric gets washed all by itself..............again on the gentle cycle, sometimes several repeats needed.

Cutting the corners almost always works