This is just based on my 2 months of online poker but here is what i have observed in that time on the subject of going/calling all-in.

It has been my experience (both through hands that I have been involved in as well as those I've observed) that the person going all-in wins fewer of the hands than the person who subsequently calls the all-in bet. After thinking about this and observing the cards that end up being shown after the hand is over it appears that many times when a person goes all-in they are doing so with what is usually the 2nd best hand and they go all-in in hopes of taking the pot right there and then hoping not to be called. This is usually done when there has already been a good amount of money invested in the pot and the person has enough remaining in their stack to make it a difficult decision for the other to call the all-in, but they realize that they probably do not have the best hand and as an alternative to checking and then having to relinquish the power in the betting of the hand they opt for the all-in route.

Conversely, the person who ends up calling an all-in bet most likely will only do so if they feel that they have the best hand. Again, from what I've experienced and observed (and I have done both; had the best hand and went al-in as well as went all-in with what ended up being the 2nd best hand and me knowing this and trying to buy the pot) the caller for the most part will usually win that all-in hand. Not always, and I have no stats to back up the percentages of this happening, but this is what i have experienced and observed.

Any thoughts?