I don’t think anyone ever intends to make mistakes and I don’t think anyone wants to make bad decisions. I don't think that the intention of a mistake is possible. It's basically an error, bad judgement or decision leading up to negative consequences and based off of the pleasure and pain principle deliberately making a mistake just doesn't make any sense.
If someone decides to jump off a building and kill themselves then I think that from their point of the view it was intended as a good decision. However, if they change their mind mid-way through the drop then their judgement has changed and they'll realise that they're making a mistake. Regardless, that does not change the fact that they initially intended their suicide as being a good decision and if they could have reversed time mid-way through the drop then they would have.
Another scenario is the concept of someone being depressed and choosing to live the rest of their life alone in their house drinking alcohol. It might seem like they’re intending to make a mistake, because surely they cannot expect sitting at home drinking alcohol to be a positive decision. Regardless, I think that from the person’s gloomy and hopeless perspective it may seem to them that recreational or social activity of any kind will simply yield further suffering. This may not necessarily be the case, but that is how it may seem too them. Therefore, for the sake of keeping one’s suffering as limited as possible one may decide to isolate him or herself from the rest of the world and drink excessive amounts of alcohol to appease the pain. Their perspective is that on a happiness scale from 1-100 they can only ever be a 2 and that leaving the house will put them at a 1.