The only 'con' I've encountered is a lot of ongoing change. It's not unmanageable, but it is persistent.
The marketing industry is changing because of AI. We've had to pivot in our services and focus to adapt.
Departments within our company have been overhauled in the last year or two. There's still some growing pains as we refine our processes.
Much of our growth and direction is a 'work in progress.' We have several things going for us that work really well, but things are continually being optimized.
I'd call it a challenge more than a 'con.' But if you're hoping to join a company that has all its' processes written in stone, this isn't it. If you enjoy more of the startup feel of figuring out how to build and optimize as you go, you'd fit in well.