I think it depends on the person and what their reason is for wanting to ctb. Everyone's situation is different. Some people may regret a past attempt especially if it was done impulsively. They may later realize that they didn't really think it through and ctb isn't the best option for them.
Some people are able to get the help that they need after an attempt. If they are able to get help and solve the issue that is the cause for their ctb, and they have hope that their situation will improve, then they wouldn't make another attempt.
On the other hand, if someone isn't able to get the help they need, and they feel their situation is only going to get worse and they are trapped, they could make another attempt if they get desperate enough.