Pros
I waited until I was 2 years in, so that I would have a good perspective to write something... and this company has significantly changed in that time... it has always been fast-paced (which I view as a good thing, but not everyone will), but I'm in awe of the agility and dynamism of the employees. The way that we solve problems and generate growth is constantly improving... and even people who did one thing one way 12 months ago, continue to grow and may have a completely different (and usually better) method now. It starts with each employee... and when you aggregate that across 1,500 employees, it is powerful.
I think that this is the real reason that ZoomInfo has been so successful... whether that is at bringing new people from acquired companies into the fold, or rolling out new products, or generating new sales, the "improvement" culture pervades everything.
I always used to think of great jobs as "what can I learn for later in my career" and ZoomInfo provides everyone who works here an environment where they don't just see what great it... they are expected to be great.
Cons
I think that the fast pace and focus on improvement isn't for everyone. In my opinion, everyone thinks that they want to be on a winning team... but you should really ask yourself: "are you excited to put in the work to be better?" "are you willing to be uncomfortable and try new things?" "do you want people to challenge you on things that aren't great?" "are you willing to accept that good enough isn't really good enough?"
That is the culture. Some people will find it a positive... others won't.