Graphical battlemaps are the single biggest GM noob trap
>placing ugly jpegs on a roll20 board to pre-arrange your scenery
>curating a collection of artisanal premade battlemaps (that you will never be able to kludge into your campaign)
>scrambling to come up with content when your party decides "nah, let's not go to the spooky graveyard"
all these things are a huge waste of time and energy