Unfortunately quality and earning money are only loosely correlated - especially for Google when they can pour money into making something good, but baby necessarily figure out how to make it earn.

And it also seems if it's not a $100 m+ business they lose interest very quickly. So even good things that could run somewhat cheap of optimized end up with no long term place in the Google ecosystem when they fail to make it big.

... That all said Google kills perfectly good things because they have a few internal rules that encourage it: that there can only be one of a system (dunno if that's applies to product but they seem to always want to consolidate every few years) and that stuff cannot be unowned so reorgs => kill products that don't match the new org structure. That and they incentivize pumping out new products with their promotion process - whether or not they really needed yet another chat/vc/etc product, someone probably figured they could climb the career ladder by shipping another one.