everyone has diff opinions of defoliation. imo. some plants benefit from it even if heavy and some hate it and it will hurt your yeild.
when running new genetics ill defol half and only light defol the other half and see which does better. then in following runs with that strain ill do whatever it liked more. i pack my 5x5 so i have to defoliate fairly heavy or else its shade city. i tend to keep the fans on the top of the bud and trim out any that are shading other areas or causing overlap. once you defoliate the fans will come.back again in about a week or 2 you can remove the trouble ones then leave it alone for.the rest unless.you have to pluck a leaf or 2. thats me tho. others will argue that but its good to get some diff opinions and decide for yourself.
outdoors you dont have to defoliate as much/at all as the sun moves through the sky and illuminates the diff areas of.the plant through the day
our grow lights are stationary (for the most part unless on rails/movers) so the light hits where it hits and thats all folks.