Checkmate in two moves more leads to a "Puzzle Failed"

I may have talked about this before but in many puzzles if you find a checkmate that takes a couple of moves longer than the correct answer you fail the puzzle. This makes no sense because the objective of chess is to checkmate, not to checkmate in a certain number of moves, therefore this feature makes no sense and moves that still lead to checkmate should at least get a "Good move but you can do better", as it is completely impractical to look for a checkmate in less moves if you have already found a checkmate.

Often the checkmate in the shortest possible moves is forced while the longer one is not (i.e more variations)
Another reason is that while executing a longer checkmate you may run out of time...

In a lot of cases, I've found, that's not really true. So I'd be at the end of the checkmate sequence(so something like 3+ moves into the puzzle) and I'd be at a position where there's a really obscure way to checkmate at that point or a 2-move sequence that also reaches checkmate that would be a lot more obvious and I would see first. In those cases, if I go ahead with that, I'd get a puzzle failed. In a lot of those cases I've tested them against the lvl 8 AI and it wouldn't find a way to avoid a checkmate, so it's definitely still forced.

Also, there are cases where the puzzle is flat-out wrong, in that the same length of checkmate sequence still gets you a straight-up "puzzle failed". I posted one here:

http://en.lichess.org/forum/lichess-feedback/puzzle-23967-considers-a-correct-solution-wrong

Though I never got a reply

it is the main goal to check mate in the fastest way. Chess it wins, but it can be faster.I've seen thisto many times.

JUST accept THAT YOU didn't find the best answer. Now stop spamming these treadhs please. Thank you

DaanNoordenbos, I accept that, that's not the point. The point is that there's a whole class of moves that gets you a failure(longer checkmate sequence) when it should be "good move, but you can do better". If getting a checkmate in 4 moves instead of 3 is a failure to solve the puzzle then there's no point to "good move, but you can do better" because that's pretty much one of the best scenarios for it.

You need to mate in the fewest moves thats the puzzle.

If that's the case, then remove "good move, but you can do better" from all puzzles

GM01 often the shortest checkmate possible is easier to see, but not always. That is why I created this thread. Also a longer checkmate generally won't take much longer to carry out because you have (or at least should have) already calculated all the variations of a forced checkmate and therefore can play moves pretty much instantly.

Daan Nordenbos the main goal of chess is to checkmate, there is no rule dictating that you get more points or something for a faster execution. Also the point of these chess puzzles is to get better at tactics and calculation. In a real game it is most practical to go for a win when you can see one, rather than spending ages trying to figure out whether or not you could have done it quicker.

Also you said that the goal of the puzzles are to checkmate in the shortest number of moves possible. As far as I am aware this isn't said anywhere on lichess, and the general assumption for a chess puzzle is you have to play to try and win. A checkmate in more moves than the shortest possible win is still a checkmate and therefore completes the goal of the puzzle (to win). I do get that there are benefits for trying to figure out the faster win, however it is impractical to constantly be double checking to see if your win is the shortest win possible hence why I believe you should get a "Good move but you can do better" comment.

As for the comment I am spamming these threads, I don't really see where this is coming from. I may have posted one thread about one specific puzzle where a checkmate in one move less was considered a fail, but at that time I believed it to simply be a fault of that individual puzzle and most of the comments where in agreement that it should be fixed (as far as I recall at least). I posted this thread after I realized that this is a consistent error and so far no one has provided an adequate reasoning for why puzzles should be failed when the user doesn't see the slightly quicker checkmate.

Sorry if this post was a bit long :)