Getting your doors to look streak-free requires a lot of practice but after a few attempts you’ll realise nothing is impossible.
Use a mini foam roller to apply the paint instead of a brush. With a roller, you will get a nice smooth finish and no visible brush strokes.
Be generous with the paint on the roller and start with the raised sections on the door. Roll from left to right on the cross sections and up to down on the sides.
Use long strokes. Apply even pressure throughout.
For the inside panels, begin with the bevelled edges. Run the roller into the bevels to coat them, and then roll over them (with no paint on the roller) to smooth out any uneven marks. Move the roller across the interior panels from left to right.
Go one panel at a time (starting with the raised parts and ending with the inside panels) so that everything gets as evenly rolled as possible.
After one coat, you will see some unevenness.
After the second coat, you will find no brush markings or streaks in the finish, and the door looks even from all sides.
(All images courtesy pixabay.com)