Alphabetize my Dvd's

[BMAD]

My DVD Shelves used to be organized by genre and frequency of watching. Now that I spend less time watching DVDs I find myself desiring to arrange these DVDs in alphabetical order. I don't care if they are left to right OR right to left, i am not that picky. To arrange my DVDs with precision I will take one DVD off the shelf and place it in the correct spot back on the shelf. If I have 11 DVDs what is the most moves I can expect to make? What if I had two shelves of 11 DVDs each?

[BMAD]

On 8/5/2017 at 11:40 AM, Indra said:

For the shelf with 11 DVD's, the most moves you would need are 9 moves.

For two selves, the most moves you may have to make are 19 moves.

I like the solution of 7, could you explain why it isn't?