"wHy DIdn'T hE bRInG aNy SUbs oN?" is the other refrain of the football ignoramus. I'm surprised you didn't call him "stubborn" too, the unholy trinity. Subs are not some automatic panacea for everything unless you don't know anything about football. Sometimes the team is doing OK and doesn't need disrupting. Other times changes to the existing personnel is a better idea. He made three tactical changes on Saturday and none of them really worked but I see what he was doing.
It was just one of those days, a game of fine margins. We get a couple of them EVERY SINGLE season and sure as night follows day we get idiots on here declaring it to be the manager's fault like football is some binary exact science.
It's not Pep's genius every time we win and it's not his fault every time we lose. He gets judged on the sum total of all his decisions on and off the field because the majority of them pay off.