Silos.
The further you are away from Andover, the less your contribution to the company is recognized.
Network stability is a problem, making it difficult to get your job done.
Mercury demands your life (forget any sense of work-life balance) and in exchange you get an insulting raise.
Too many people telling other people what to do; not enough people getting the work done.
Working at Mercury is like being at a small company that never figured out how to grow up. Chaos and dysfunction are far too common.
A lot of rude managers (including people with director and above titles) that don't know how to treat people with basic human dignity.