The company is stuck with a start-up mentality even though it is no longer a start-up but a large global enterprise. You'll get people throughout the company asking you to do a task that takes several days at 5:00pm on a Friday and expect it done for 9:00am Monday and it is always "urgent or business critical". 90% of the time, it is not.
The pay is very low compared to the amount of work you have to do. Essentially you will be involved in most aspects of the technical operations, though it's great for learning, it does take it's toll on you over time. This is the type of company you work at for a little while until something better comes along.