Tennis uses multiples of 15, but only up to 45, calls other points weird names, then closes a set, which has to be repeated at least 6 times for a separate scoring, with said scoring also needing to be repeated AT LEAST 3 more times, but can be dragged out ad infinitum.
Even table tennis has the decency of using a straight scoring system where 11 points wins a set and 2 sets wins the match.
Here’s the way I think you get to the tennis scoring system, which may not be accurate:
First, you start by scoring based on a clock face - in 15s, aiming to hit 60 (four 15s). So a quarter of a circle per point, and a full circle to win.
But, then you have the rule where someone must not hit 4 scores (60 points) to win but must have have 4 scores AND be up by 2 scores, not just 1. So for example, if both players are at 45 points, one of them needs a net of 2 more scores to win. To make this work and keep 60 as the number to win, you need to squeeze two more scores in between 45 and 60. So instead of 15s, you go by 10s. Of course two tens below 60 is 40 instead of 45, so you adjust the 45 down to 40. Thus the possible scores go 0,15,30,40,50,60.
Except once both players have at least 3 scores (40 points), all that matters is who is ahead, since they both qualify to win as soon as they are two scores ahead. Therefore there really is no 50, as you either go from 40 to win, or you both hit 40 and then the scores don’t matter and you just talk about who has the advantage (one score ahead). So you have 0,15,30,40,Win
Man, if only the decimal system had been invented before clocks, they could simply make it “4 points with at least 2 point advantage”, like 4-2, 5-3, 6-4, etc.
There’s still the whole mess of using 2 extra layers of “score this much with 2 point advantage”, because I guess people don’t have anything better to do than watch a game go on for 6+ hours
They really didn’t, though. You think the average factory worker was in the stand watching their betters hit those balls? And look at cricket ffs!