My take and experience. Although I rarely try to evaluate the “signs that the money wouldn’t be wasted,” because as mentioned by a lot of posters in this thread, the chances that anything will ever come out of the labor-of-love types approach zero.
But if it’s a cool concept, I may chip in $10 or less because I want to see more of that concept / style / genre get recognition even if that specific iteration is probably doomed.
But if you look at our thread about Free Video Games, there are a substantial number that were being given away for free because the creators burned out / gave up ever reaching a finished status and end up releasing them in a “good enough” version that was far short of their ambitions.
Or similarly, end up releasing something that feels like an extended prologue or intro sequence and tease that with more money they can release the rest, or next “chapter”.
My bigger experience was with things like LFG which ambitiously announced that they would release a (short) motion picture version of their comic with fan-funded monies. The result? Two animated music videos/teasers, which while fun, was NOT the premise. Claims were made for years that they were having developmental and funding issues, none of which were ever resolved before the whole comic going on indefinite hiatus last year.