The size also contributes to IBM's faults. Everything has a process and many small issues can take days or weeks to resolve. There is a very "not my problem" mentality unless someone is going to get paid for doing it.
Personally, when I was hired I signed a document that had an on target earning of a certain amount. Within 2 months my commission was placed out of my control and I was surviving on base pay alone most months. After that my manager quit and I was restructured. This happened three times. The company had a lot of trouble with the acquisition that I was hired on the tail end of.
In the end I found myself in a role I really enjoyed, but the company wasn't ready for me to be a part of it. They laid off several of my coworkers and relayed their work to me without any sort of compensation to match.
The company has no culture. Before the acquisition, the company was a cool start up with team gatherings and friends abound. Afterwards the office was dead silent every day and people left in droves. No holiday party, no happy hours, no drinks after work, no socializing. Not the best environment for anyone looking to be friendly.