Pros
I worked for Qualys for many years before abruptly leaving after I could no longer handle the stress fostered by poor senior management decisions, lazily thought out technical decisions, and the abundance of the half-baked "proof of concept" features inevitably being forced into production. That said, in the beginning things were great. When I started with Qualys there was a great sense of opportunity and excitement about new products. My managers were some of the best that I ever worked with and seemed very concerned with my growth and morale. I always felt appreciated for my contributions and was offered great incentives to continue performing at a high level. I was with the company during the IPO and received great options, and was, like many others, focused on doing the best I could to help the company grow and keep the stock price on the uptrend. This is when I started seeing things change for the worse.
Cons
Slowly, after the IPO, the culture shifted to one where the only thing that mattered was delivery dates and getting fragile, hacked-together code out the door. Technical debt began to accumulate at a ridiculous rate. Those aforementioned managers that I enjoyed working with started leaving and were replaced with much less experienced and less capable people. Regular 45-50 hour weeks gradually increased to 70+, with people reaching out at all hours. In the end, I felt like my job was to put out fires rather than to proactively do any meaningful work. There was no change in sight and morale was at an all-time low. It was truly sad to see a company I loved working for change into a place I dreaded working.