Cask strength - why 60 ABV?

Being largely double distilled, the middle (useable) cut from the second distillation of most Scotch Whiskies tends to be around 68-72%abv. A few distilleries fill casks at this strength "straight off the still" but this is not the norm. The vast majority cut the whisky before filling to a strength of around 63.5%abv as this is deemed by much of the industry as the ideal achohol volume for maturation. A cynic might argue that it has more to do with it being a good strength for maturation speed rather than quality but that’s another discussion all together ;-).

@Max What @Stu_R said! I also seem to recall that the "angel's share" is higher (percentage-wise) when you go above the mentioned "ideal" range of ABV for maturation, so it's a convenient intersection of maturation, quality and minimisation of alcohol loss.

Thank you, guys, that makes sense