In my opinion, I would recommend that Amakna will be creating a option box which is called Achievement Reminder, where almost similar as challenges in fight.
The main reason I would propose this, is because most of the players may not know they have failed the achievement yet they still go on with the fight, after they ended the fight, they didn't know what is the actual reason of failing the achievement.
I'd say Dofus can make something similar as Defence of the Ancient (DOTA), League of Legend (LOL), and so forth by giving game replays to players after ended the fight, but this is literally impossible for Amakna team since it requires high-level technology and expertise.
For now, I think Achievement Reminder might be useful where players exactly know when the time they failed achievements and make improvements in the next run. Please take my idea as consideration, thank you.