The full phrase is
„Leider, leider sagt der Schneider, macht der Schuster keine Kleider.”
and is a simple rhyme meant to gently/jokingly tell you that you can't have everything you want/just the way you want it. A simple translation is "Unfortunately, says the tailor, the shoemaker doesn't make clothes," but it loses all rhythm and rhyme in the translation, and therefore all its charm.
Either you misheard the "Beschneider", or the joker was turning it into a far cruder joke by turning the tailor into a performer of circumcisions. "Leider, leider, sagt der Beschneider" is still kind of funny in a "things you don't want to hear from someone performing delicate surgery on important parts of the male anatomy" sort of way, so if you heard that from the guy who made the very bad chess move, it may have been a joking way of saying "Oops, I just messed up really badly!"
But that's quite far from the original version of the rhyme, and I suspect you simply misheard.