From what I know, disability is intended for people who are going to be disabled for a long while/permanently.

Depending on your condition, you will have to re-certify. For me, it was after 3 years.

How easy/hard it is to get really depends on the person & health condition(s). I've heard that most people get denied on their first try, but that was not true for me.

When I applied, I got a response within 4-6 months I believe, and I was approved. After 2 years on disability, I was eligible for medicare