Cutting is more important than writing. If you cut without writing you can still be a great editor. If you write without cutting you’re drowning the world in unfiltered garbage.
Some people call editing your own work “murdering your babies”, forgetting the part where you reread the work the next day and realise that those weren’t babies, they were ugly chest-bursting parasites which came out in the wrong place, destroying important structures in the process, horrible acid-dripping abominations and you’re much happier now they’re gone.