This questions is so important and there's no one-size-fits-all answer. Therapy has been proven to be helpful for a wide range of personal and interpersonal issues. Yet in our culture there's a lot of uneducated information about what it actually is. To further complicate the issue, there are different fields, methods of practice and every therapist has their own individual differences. It's important that we choose the right therapist if we're going to make a commitment to our mental health.
For this reason I require a free initial consultation with prospective clients before we begin therapy. It's critical that a therapist and client establish realistic goals and get on the same page about how to reach them. While its uncommon, there are times when I've shared with a prospective client at the end of this consultation that it doesn't seem that the issue they're wanting help with is something that can be achieved in therapy. I've also told prospective clients that it seems like we need a second consultation to make sure that this is a good fit.
The point here is that being on the same page with your therapist is critical. There is no contract for number of visits even if it is a good fit. You are free to end therapy whenever you want to.
Therapy might be a good fit if you feel as though you have tried everything you can think of to make necessary changes and continue to feel stuck. Good therapy should be a process that includes lots of focus on patterns. If you want to reflect on your patterns because your life is stuck, therapy might be a very good fit.