Spent today painting downstairs bathroom. It now takes at least two coats of paint to paint a room. Brand doesn't matter. I've used Gliden, Olympic, Varathane, Sherwin Williams, Behr, Ace, Pratt and Lambert, Duron, and none cover in one coat. When water based (latex) paint came out, one of the big selling points was "one coat coverage." Fast forward fifty years, and now it takes two coats to do the same job. Of course this means you have to buy twice as much paint to do the same job as fifty years ago. And it does cost a little (a lot) more now than it did fifty years ago. Old enough to remember "one coat coverage." What progress the paint industry has made in the last fifty years.