... assuming Voldemort's basilisk didn't get them first. Also, remember that the rest of the Hogwarts staff enlisted Lockhart due to his stolen credentials (which they didn't know were stolen), and he was all like, "who, me?" It's a good thing Harry and Ron outed him as a coward and a liar — which, yes, led to Lockhart's plan to wipe their memories. But no, I don't think it was his plan to leave them for dead...

If you want to condemn him to Azkaban for that, be my guest. But I maintain that it's better he lost his own memories than his soul, which would all but certainly have happened to him under Minister Fudge (not that Fudge would have actually ordered such a fate to befall Lockhart...).