The obstacle I met when I was working on a project was the discrepancy between the members. It is very usual that one group of members have more than one opinion on the same things. And everyone think their opinions are right. Nobody would say” Mine is wrong”. So then they will discuss, but sometimes the discussion does not go well. Some people still won’t change so finally they decide to quit. I feel whether their opinions are right or wrong, loss of members is not good for a team and project.