If your painting plans include a different color ceiling, or possibly an accent wall, then the corners are always the trickiest part. Obviously, taping can help, but I’ve often found walls are rarely straight and sometimes taping highlights the unevenness of the wall and cutting in with a brush often looks better.
But sometimes you can avoid situations like this just by thinking outside the box.
One of my current favorite techniques is to move the transition away from the corner and onto a flat portion of the wall:
This makes taping easy, creates a clean line regardless of the condition of the drywall in the corner, and- in the case of the ceiling line- can create some interest by appearing to “heighten” the ceiling.
Makes my life easier and looks good? I’ll take it.