The first time in a hospital for me wasn't really my choice as much as it was a "professional's".
The second time kind of was because my friend talked me into it, and I don't blame him for it. The first time, I needed help, sure but I don't think I needed to be committed. The second time, I was actually suicidal. My friend walked in on me as I was doing it. He stopped me and talked me down. Then he helped me tell my fiance and the next morning my fiance drove me to the front door with my stuff, gave me a kiss and I walked in.
When someone "needs" the help is subjective to that person and their situation. If you feel you need it, check into it and see if you can. If you don't feel like you're quite at that point, then don't. It really does depend on what you feel you need.