If you ask me it works when it ties into the theme/story of it.
Castle of Tempation for example makes sense given that it's supposed to be a test of willpower/endurance or whatever where giving in fails the test.
Other then that maybe a better way to implement this is to rather give a small reward for losing while getting a higher reward for winning.
idk, I'm not a game designer o.o
I agree here as well, how worthwhile the loss-reward idea is depends a lot on the context. CoT works well with what it does, all things considered. I will say that the problem is less so that games with the loss-reward system are bad in and of themselves--the issue is that they are the standard. The fact that a very, very large majority of H-games (that I've seen at least) fall under that category leaves a lot to be desired. Also, galleries are a great way to balance out the whole loss-reward issue. If you lose, the thing you lost to is unlocked in the gallery. You win, everything up to that point is unlocked.
With all of that said, two great examples of what I'd prefer in most cases are
Succubus Affection and
FM v. CDW2. Both games have loss rewards, but there are also rewards exclusive to doing well, with the former being attainable through the second method so loss is never mandatory, treating the reward as a consolation for loss and incentive for winning rather than an incentive for loss and discouragement from winning. An honorable mention is
Princess Reconquista, in which there is a HEAVY focus on rewards for doing well and little-to-no consolation. In terms of how the content is distributed, it's not my favorite method, but motivation to push forward is the goal, so I have no real complaints.
Edit: To bring up an example parallel to the others,
Alien Quest EVE. I love this game so much. I love its Metroid-esque style, I like its combat system, I like its enemy diversity, I like its inspiration from the Alien film series, it's nearly perfect for me.
...Except for how you unlock the gallery.
Beating such a difficult game is rewarding in and of itself, but the fact that the gallery scenes don't unlock unless you specifcally trigger the scenes by taking a hit (which is most of the time is a coin-flip between triggering it and taking damage) is oh-so-infuriating. I can tolerate loss-reward systems as long as you don't HAVE to lose to unlock everything. But if you have to actively do terribly to unlock everything and there's zero alternative, then that just pains and angers me to no end.