I have a "smile test". If a bike doesn't make me smile either when looking at it or riding it, then it goes.

Since I haven't the patience or the wallet for a faithful friction era build that does both, most of my time is spent on building c&vish riders based on idle thoughts about what might be ideal (and that is increasingly with modern components). The days of finding inexpensive faithful restoration worthy bikes seem pretty far in the past, or so much of a rarity that I've moved on by necessity.