Things seem to change pretty frequently. What got you ahead yesterday won't necessarily get you ahead tomorrow. It's a high-growth, responsive company, so maybe it has to be that way, but if you're looking to hone mastery in a single narrow skill for the rest of your career, this may not be the place for you.
HC will support you financially in self-education, but it's probably up to you to figure out what that self-education looks like to further your career. (That can be both pro and con.)
There are a lot of pieces in the Health Catalyst solution stack, and it can be hard for newcomers to see what they are and how they interact. Communication attempts are made; people present both high-level solution and low-level technology updates in our frequent all-company meetings, but even the intro slides often presume a certain level of understanding that not everyone has.