Oh man where to start:

Not wanting to use LINQ because he did not wanted to "download external dependencies"

Not wanting to use prepared statements on their php sql code, and refusing to use pdo because they will "always use mysql"(moved to postgreSQL shortly after I left)

For some reason including a php file that only had ?>......thats it....only ?>

Use c++ but refused to learn oop and use structs for everything, importing stdio.h and printf everything.....like really?

Maybe just nitpicking, but refusing to use the recyclerview pattern on am android app. The implementation was faster after I made the change.

Importing a library for promises instead of using the ones already in the language(JS)

Changing the style of aaaaall p tags instead of using classes as well as refusing to use divs in place of p tags...well...fuck

Not indent his ASP classic code

Use notepad on his asp classic code

Use ASP Classic in 2017, even for new projects