In a start-up company, one can get through levels smoothly the talent and hard work are constant, while in large organisations, it would be harder to get your way to the top, however, I believe there is a risk element associated with being in a start-up company, and it would depend on the person risk appetite. In terms of experience, a large company has lots of available knowledge to provide to employees, while in start-ups, you may well be on your own, with more chance to do something new (but that does not mean that a mature company wouldn’t give you the space for creativity, it just means that in a start-up you may need to work various tasks, and gives you the chance to do different roles).