What I don't like about this terminology is that I associate these "schemes" with a malicious actor. Someone trying to scam you. But often that's not the case with these crypto projects. Often, nobody is explicitly trying to scam anyone, but everyone looks out for themselves first and wants to make money, which inevitably results in other people losing money if they are too late.

If a traditional startup is valued at $10M, I'm sure many founders would choose abandon it and take $5M in cash if only they could. The difference is that the liquidity is not there, so the option doesn't exist. In crypto, protocol founders may not start the project with the goal of abandoning it, but once they can choose between cashing out with $5M by abandoning it, they take that route because they can. People then call this a "rug pull" or "ponzi scheme" but I don't think the intentions are the same.