Pros
They give you the ability (or obligation) to work on several clients from several different industries. You might work with all sorts of clients ranging from small, to large, to boring to quirky. There is freedom to input on how things should be done. You will eventually learn the basics of your job function because you need to in order to do your work. Processes are set in place that guide you in basic practices so you can refer to them when confused.
Cons
You will be forced to learn on your own or get in trouble. You will be expected to perform certain new actions, but will be given no resources or guidance to complete your tasks. While there are processes set in place to help in this matter, in an industry like internet marketing, processes become outdated very quickly. Employees are expected to redefine processes as needed, while taking care of their employees. There is no true intrinsic value for working at the company. What does the company provide to you that you can't get elsewhere? There is nothing. Senior management has no direction for the company and it shows in employee turnover and morale. Leaders do not inspire or have any desire to motivate employees to work harder. There is no clear career paths, and promotions are unclear and raises are pathetic. The company runs on a very 'break-even basis' and therefore constantly feels as if financial cuts will need to be made. Overall, the mood and morale of the company is low and uncomfortable, while being covered by optimistic-acting leadership. Leaders do not know how to resolve complex issues, and expect employees to lead the company into a new direction with no clear goal or reward. The company has no culture.