Oh man, that's a solid tip. I always give the collet a quick twist by hand before it goes in the spindle. Found a tiny chip stuck in there once that would've wrecked the taper. Your fingers find stuff you just don't see.
Yeah, it's crazy how that works. I do the same thing with my phone case, always find pocket lint in the charging port before it causes a problem. Wonder what other small checks we're all doing without even thinking about it?
That hand check is pure gold. It makes me wonder how many crashes start with a simple part not sitting flat. Do you run a similar check on your workholding? A quick wipe and a push on the part before you clamp down can find a stray chip or a burr on the parallels.