In verse 5 of Titus 1, Paul says that he left him there for a reason and that he already told him what to do. "The reason I left you in Crete was that you might straighten out what was left unfinished and appoint elders in every town, as I directed you." (NIV) So Titus already knew what to do, but it was hard work, and he was getting discouraged. Boy I can relate to that! The work gets hard, with very little results, and I get discouraged too and that's when I throw myself a big ole pitty party. Streamers, balloons, the whole works. So I don't Blame Titus for feeling down, but Paul just says, "GET BACK TO WORK." Ya know, you never really see a lot of mercy come out of Paul.
So what is he supposed to do? "Straighten out what was left unfinished..." Or your version might say, "to set in order the things that are wanting..." That phrase "Straighten out" or "Set in order" (Another Greek Freak moment) comes from the Greek word EPIDIORTHOO. That is where we get our word orthodontist; which is someone who straightens teeth; or orthopedic, like a mattress, that helps to align or straighten your back. This is a medical term!! Why does he use a medical term to instruct Titus? I think it is because these people are broken and need to be fixed.
It's like they have a broken arm and Titus needs to set it.
It's gonna hurt and it's gonna take time, but if you don't straighten it out; then it will always be wanting, unfinished or just plain crooked.