As for your comment about nontrivial puzzles - absolutely! 100% agree - the joy in a lot of puzzle games like bejewelled is unexpectedly clearing half the board with a clever move!
* Solve two pieces
* “Oh, maybe if I did it the other way around I could get that in one” <Reset>
* “ok that worked but I wonder if it’s different if I did this…” <Reset>
* “Ok actually all of those have been exactly the same number of moves, but how about if I just reset and do the first again?” <Reset then complete>
I just mean I’m not sure I would class the above as “4 attempts” to show difficulty as you are just using it to test scenarios (ie the above person found it trivial even though it took four ‘attempts’)