It is true that perseverance is one of the attributes of a good freelancer. However, it is akwags better for freelancers to know when perseverance will stop learning it becomes a burden to the freelancers. You need to make sure that you are not enduring what you need to take actions on. Clients should not be talking down on you without you replying all in the name of being preservered. When it is not yielding any positive impacts, you can opt out.