Baseball Fact: With 2 outs, if a runner cannot easily make it to 3rd base without sliding he is better off staying at second base. Why?

Because runners can run on contact with two outs, almost every ball hit that would score a runner from 3rd with will also score a runner from 2nd.  Therefore, with two outs, the only real advantage to having a runner on third base over having a runner on second base is that some wild pitches and some infield singles allow the runner on 3rd (and not the runner on 2nd) to score.

Admittedly, some infield singles and infield errors are the exception to this rule, but these scenarios do not occur frequently enough to justify risking a base runner being thrown out at 3rd base with two outs.

For these reasons, the general rule for taking third base with 2 outs is that if a base runner can reach third base without sliding he should take the extra base. If the runner needs to slide to be safe, the risk does not justify the reward of running.