Why bother planning?

My friend thought that my trip is a perfect example of why planning doesn't necessarily lead to better vacation trip experience. He pointed out how much time I spent on planning my HK trip ever since 6 months ago using technologies like Google Calendar, IM and email. Yet I still experienced frustration, anxiety and disappointment for not achieving all I planned.

I disagree with him, though. I think that for the among of things I accomplished during this trip, I was doing a pretty good job, and they are definitely partly the result of the planning I did. Mom was pretty happy because I spent a lot of time eating at home. I got her computer up and running in a stable, secure and easy to use fashion. I got to met as many friends as I could within the 2 weeks. I participated in my friend's dance performance. I had good time having trips at places outside Hong Kong with friends. I got several beautiful costumes made, and I brought a lot of stuff that I will use in the coming one year. Without planning, I may not be able to accomplish half of them.

I guess the problem is not on the planning itself. It's just that my plan was too ambitious.