I consider myself concerned enough about Google, and supportive enough of having Firefox as an alternative, that I feel somewhat guilty for giving up on switching to Firefox about once a year (at least). And yet I keep doing so, because for whatever inexplicable reason I prefer Chrome enough, or dislike Firefox enough, to keep switching back to the former.

While your comment prompts me to try again and figure out why this is the case exactly, Google's marketing is not the reason for me (and, unfortunately, others too).

If I had to guess, I'd say it usually boils down to a feeling of clunkiness and weird hogging of memory/processing, whether true or just perceived. I've read some threads that indicate this is a problem for Mac users in particular, but I don't know if this is actually true.