If you make your doors correctly then you won't see the glue line in a few months. You need to account for the water in the glue. It takes about 3 days for the water in the glue to migrate out of the wood. After that you can do your final sanding and expect to not see the glue line to show up down the road.
If you are buying your doors it's a good chance they aren't putting glue on the shoulders of the door, just the stub tenon. Plus most don't clamp their doors until the glue dries. Usually clamped long enough to shoot a couple of nails in the rear to hold them together. This produces a joint that isn't tight and leaves a glueline that is greater then .002", which is the max for a good yellow glue joint.
I make my own doors and they get glued in clamps for a minimum of 45 minutes. Then they are sanded with 120 grit and if they are painted I put a small amount of putty on the joint whether it needs it or not. Lacquers have poor bridging abilities and will find any type of gap, even if it doesn't look like one. Then I will build the cabinet(s). By the time I come back to do the final sanding (150 grit) a few days have passed and the moisture from the glue has migrated out of the wood and won't pose a problem after sanding.