“time-consuming” does not cleanly encapsulate difficulty, because lots of easy things are time-consuming too.
Perhaps “slow to reward” is a better way to gesture at the phenomenon you mean? Learning a language takes a high effort investment before you can have a conversation; getting in shape takes a high effort investment before you see unambiguous bodily changes beyond just soreness. Watching TV and scrolling social media are both time-consuming, but I don’t see people going around calling those activities difficult.
“time-consuming” does not cleanly encapsulate difficulty, because lots of easy things are time-consuming too.
Perhaps “slow to reward” is a better way to gesture at the phenomenon you mean? Learning a language takes a high effort investment before you can have a conversation; getting in shape takes a high effort investment before you see unambiguous bodily changes beyond just soreness. Watching TV and scrolling social media are both time-consuming, but I don’t see people going around calling those activities difficult.