I asked my boss to pay for it (he did) but he said: do you use anything to organize your life and projects right now? If you don't, I don't think a PalmPilot will help you.
He was so right.
But there are exceptions. I never had an address book or calendar until I had a Palm Pilot. It might have just been that I was becoming an adult at the time, but part of it was probably a barrier to use factor. The Palm was a small thing I could carry to class, keep near my phone, bring to my internship job, etc. It and the need for organizing did conspire to make it my first real organizer and my first time having that information organized at all.
It all boiled down to the physical paper tradeoff: small filled up quickly/was too constraining a space, bigger was impractical to lug around anywhere.
So arguably I had sort of a broken system in place already but it became very intermittent to the point of being nonexistent in practice because of the constraints. Palm devices allowed me to fully realise the system.