I’ve always understood that D.C. and D.S. did _not_ include the repeats. However in searching around the internet, I find there is some controversy about that for Beethoven and later. For Classical and earlier period, though, without repeats is assumed unless indicated otherwise. Musically, you’re likely looking at a recapitulation of material you’ve already played twice (at least). I’d think four times (with repeats) would often be really boring.
But what works musically? Are the repeats with improvisation?
The rules may be entirely different for pop songs, especially ones that originally had lyrics.