Laid-back atmosphere--you get a lot of 'bare minimum' employees and everybody ultimately relies on the extremely knowledgable 'Brents' of every team (character from The Phoenix Project, a popular book at the company).
Low managerial oversight--unless something goes wrong, you will not stand out no matter how much work you do. There is a phenomenon of the 'incompetent manager' which often gets thrown around in casual conversation like it's a regular thing, which leads to the next point...
Low managerial accountability--Managers aren't held accountable for their decisions except in extreme cases. The 'blame football' gets passed around until everybody is so confused that nobody truly gets blamed and the same problems happen again down the line. If anybody gets blamed, it is the underlings, and in meetings where they aren't invited and can't defend themselves.
Low upward mobility--they hire out-of-house employees more often than promoting internally. On my team, it was impossible to become a 'Senior' level or get paid more, despite doing the same work. Every team's lead struggles to get money for new employees, and this was just recently made even more difficult by closing a loophole they were using to get interns.
Turnover is high--employees leave, but their spaces aren't usually filled. Workloads get cannibalized into existing jobs with no extra pay or recognition.
Low pay--in IT Ops, everybody is getting paid less than competitively. My salary rose by ~50% upon leaving. They get around this by having a 'bonus' you get every year, but it is contingent on the company's performance, and for the last 7 or so years employees have been watching their bonuses dwindle to the point where they only make a few hundred extra dollars each year.
Payroll often makes mistakes--if you are an hourly worker, you need to check your pay every single pay period to make sure you are getting what you deserve. Payroll won't entertain your problems until you get higher-level managers involved. Problems my team had in November didn't even begin to be addressed until February, and we had to push them every step of the way. They changed how worked holiday pay works in the middle of a work year and pretended it had always been that way.
Meetings for the sake of meetings--most meetings could have taken place in a simple email thread with maybe a paragraph.
Nepotism--you will see/hear a lot of the same surnames, including the eponymous one. Interns are relatives of employees more often than not.
Change--usually a good thing, but at this company they change processes and systems so often that nobody ever gets fully used to the old one before being spirited away to the new. It causes chaos on all levels.
Lastly, it is no secret that this company has been scoping out the prospects for an IPO. It will probably happen within the next year. There is every reason to believe that once this happens, they will care about their employees even less since they are beholden to shareholders. At that point, there will be an exodus from the company, as many employees are now stably just below their breaking points.