Is it common for VC firms to keep pivoting their thesis and focus areas?

Now it seems “headless marketplaces” are where certain funds are doubling down on. Previously it was points, and before that generically consumer social.

Seems better to have a core thesis vs just ride the current hot thing?

cma.xyz. Founder /paragraph, ceo /mirror, previously at Google & Coinbase 

A handful of top firms influence the narratives with their theses. The rest follow. 

Indecisiveness of focus is more common in an uncertain macroeconomic environment.

It's not best practice though.