"It helps to focus on having fun throughout, instead of doing what it takes to reach the 'goal' of orgasm.
If you're not taking pleasure in the journey — or at least indulging some curiosity — then why keep going?
Like an aging MLB player, it's time to retire the system.
In a rush to pass the specifically spelled-out bases, foreplay isn't even a priority — first base isn't something to brag about to your "bros."Moreover, the acts between first base and home can be extremely intimate, perhaps more so than sex.
This is especially key for women, who are in a relationship," not something to be shared with just a fling.
There are, as the top comment on this question notes, four bases in baseball, and these have corresponding sex acts associated with them.
"I got to second base with that girl yesterday." "I didn't think I had a chance, but I made it to third base with her last night." One of the other answers has provided a nice link to the Wikipedia entry for baseball metaphors for sex.