Tapping those booties

The answers of having more than one sex partner are manifold. One of them is to “tap those booties”. This is what some young men told me. Always having the same booty at the side gets boring for those young chaps, they say.
This goes along with a setswana saying which could be put like this:

“Always eating porridge is boring, sometimes you have to change the side dish because you could also eat pasta or rice.”

Ok.
My question was then, why not spicing up the sex life with the current sex partner? There are many ways to have sex without that it could get boring. Or not?
The answer to this can be found in another saying which says something like:

“You won’t cook everything with just one pot!”

That’s a point.
What else is to say about that?
For me, some questions are lingering through my mind because those young men say that this is a new fashion but I guess, the sayings can be dated back much more in the past.
Is tapping a booty or changing the side dish just a thing which has been there in the past or is it influenced by pop-culture, as one of my interview partners said?
And what does sex mean in this context?
An urge which can be satisfied by and with anybody?
Is it really like tap and go?
What comes next? Tap and go again?
And after that, again?
What happens if that tapping and going gets boring, too?