VCs don't invest their own money. VCs are paid a percentage of the money they invest in startups. As a result VCs only care about the quality of the investment they make insofar it helps them raise more money in the future. Because more money = more fees.

VCs care about technology sometimes, but not always. If a startup doesn't grow because their tech is bad that's something VCs care a lot about. If a startup grows fast with snake oil tech (e.g. crypto, theranos, wework) VCs will happily throw more money at them.