I was editing a block with a vertical selection. I had a list of vars in a column and wanted to preface them with a var name and operator for concatenation. I then wanted to add a suffix to the end of each line.
Inserting as I moved the cursor right, paste the length of the shorter strings, the cursor on those lines wrapped to the beginning of the line.
I have a pretty good explanation here.
I think the correct action here is the vertical select should stay at the end of each line and insert at that point (custom for each line.)