Patent Application and Rejection influencers

I think this question is too vague to be fully answerable, but I'll add my two cents worth.

• Usually how long does it take to file and obtain patents?

My experience is about 3 to 5 years, but it is variable and can be longer.

• What factors influence the chances of getting a patent successfully or getting the patent application rejected?

My opinion is that the most important factor is the hiring of a competent patent attorney or agent with experience in the specific field of the invention. This far outweighs nearly any other factor. Even when successful, I've noticed that patents obtained without help of an attorney or agent tend to be weak and narrow.