1) High Expectations - You must perform!
2) Hands off management style - sometimes, it's sink or swim, you must be internally motivated.
3) Long commute for some folks.
4) If you don't enjoy an irreverent management or working style, this is not your place!
5) You can get stuck in a role. Upward mobility within the company can be limited depending on your skill set because the company is still relatively small.