I was recently asked this and, coincidentally, I came across this explanation by Moshe Talmon:

“The ultimate test for any form of therapy is whether or not a person can utilise or sustain the changes achieved in therapy.

“Therefore, the best time to come to therapy is when you, the client, are ready to do something about your life, and if need be, do it on your own.

“The key to success in therapy is timing. Are you ready for change now?”