not worth while
Not at all beneficial to one; a waste of one's time. I spent the entire day pouring through books in the library, looking for a great reference for my midterm paper. Turns out it wasn't worth my while. It's nothing personal, but it's just not worth our while to spend so much time and money training someone who is planning to leave the country next year.
not worth one's while
not worth bothering with; not worth spending time on. It's not worth my while to discuss it with you. Don't bother trying to collect money from them. It isn't worth your while.