Over the years I've been frustrated by failures of alligator clip leads. Nothing is worse than thinking the device under test has a problem when in fact it turns out a bad test lead that are the issue.
This has only gotten worse in recent years, as most of the commercially-available clip leads have become complete junk: A few strands of weird metal inside stiff plastic insulation, with cheaply-made alligator clips loosely clamped (not even crimped) on the ends.
My old leads are wearing out so a couple weeks ago I bought some new clip leads from a reputable vendor. They turned out to be the worst ever - half of the leads had no continuity right out of the package. I tried soldering the wires to the clips but the few strands of wire did not seem to want to take solder - very odd stuff. I trashed them and went on a search for good test leads. I first sought good test-lead wire and clips to make my own - the minimum quantity of the wire was too high.