In MOBAs like Heroes of the Storm you can configure your hotkeys in 3 modes: on-press, on-release, and normal.
I use on-release with abilities that require careful targeting, which causes the press action to activate targeting with the ability firing on release. You can dismiss the ability by right-clicking too. This is usually more reliable than normal targeting since the game requires very quick interactions.
It's the same in League, they're just called quick cast & quick cast w/ indicator. And normal cast, but I think nobody uses it. I feel like on-release (w/ indicator) is more popular when people can choose, but maybe not.
I like that it's configurable. Perhaps most importantly, some abilities are hardcoded to use the sensible option when only one makes sense.
I use on-release with abilities that require careful targeting, which causes the press action to activate targeting with the ability firing on release. You can dismiss the ability by right-clicking too. This is usually more reliable than normal targeting since the game requires very quick interactions.