Company is flush with cash but is chaotic and disorganized, refuses to "grow up"
Pros
Great benefits, and yearly bonuses can equal or exceed your salary. This company is at the nexus of the PC game business, so your work can have a big impact if you carefully choose the right project and people to work with.
Cons
Placing any bets on a long-term career at this random and cliquish company is probably as wise as betting all your life savings on a single spin of a roulette wheel in Vegas. At this point Valve has devolved into a place you work at to pad your resume and make some bonus cash. Be prepared to be let down once you're inside. The basic idea of Valve works well with small (30-50 person) companies, but utterly fails to scale to a company with hundreds of people. The board and their closest friends have become extremely wealthy, so they have very little incentive to fix the company. This organization has a purposely opaque, hierarchical, secretive, and very rigid management structure. Many of the board of directors and their friends are utterly capricious and conceited. The longer an employee is at Valve, the more they singularly focus on protecting their yearly bonuses and the less they care about basically everything else. Some projects can go on literally for 5+ years wandering around pointlessly without shipping, with little to no direction, and no accountability. This company is terrible at writing and shipping large scale software, and sneers at words like "software engineering", "architecture", and "testing". The random mass firings of 2013 tanked moral, and the stream of talent leaving the company during 2014 didn't help. The yearly review process lacks feedback, transparency, and coverage. This company has no formal HR, so good luck if you need to give genuine feedback about troublesome coworkers.