I think the important thing in all these cases is that the student is
advised about the situation, there are some schools that will just keep taking peoples money without saying anything and IMHO this is unethical. If you have explained the situation and the student wants to continue that is fine. This even applies to those who are nightmare students, they can either listen to what you say and sort it out, or ignore it in which case they just don't get to solo standard - and I quite agree that you no longer need to give 100% - if they don't want to why should you?
