I'm really shocked to see Quietly have such a high rating on Glassdoor. My experience, and the experience of many of my coworkers was overwhelmingly negative. Apart from there being no work-life balance and little acknowledgement from management when this is brought up as an issue, many senior people (all white men) at Quietly are manipulative, and often abusive. This is framed as "constructive feedback", where they (and your other colleagues) freely criticize you on things that have nothing to do with your work performance. This includes everything from how you sit in meetings, your attire, the way you speak, your facial expressions...essentially everything that makes you an individual.
There's also a lot of ego at Quietly. You will work with some highly intelligent people who are quick to flex their ego and show you where you rank within the company. There's a culture of intensity and internal competitiveness, which is strongly upheld by a number of young mid-managers (with no previous experience managing people) who will undermine and undercut you in order to advance their own careers. When this is mentioned to senior management (as there is no HR at Quietly), their response will be "we're aware of this, it's unfortunate, and we hope to train X out of these behaviours". No further action will be taken.