This person is using the right finish. I exclusively refinish front doors in Cincinnati Ohio. I use gloss marine and thin the first coat with naptha and and japan drier to speed up the drying. I apply four coats including the bottom so water doesn’t wick up from the bottom of the rails. I use a gallon of gloss for the first 4-5 coats and filter those with cone filters. I use gloss because it has no silica sand and is totally clear. I sand with #220 between coats. The final coat I filter with ladies nylons. I brush over all the coats with a bristle brush that has NEVER been used for paint. Lift and back brush going from dry to wet otherwise varnish dries so fast you will have starting lines. Feather in going from dry to wet. Use a FRESH quart and filter with ladies nylons. Let the varnish dry for 2-3 days. Install new sweep and jamb weather stripping. I prefer gloss, clients often say I can’t handle gloss but when they see it they see the beauty of it. Re-coat with marine varnish every 4-5 years. The door will look great when you are willing the house to you’re children. Good luck with your project