Jerry is a successful lawyer by middle class standards. Successful enough to avoid taking the tube to his firm's City offices. He arrives at 8am on the dot and rarely gets home before his wife and kids sit down for their evening meal. His day consists of meetings, court days (his favourite) and reading - lots and lots of reading. Jerry studied the classics at Cambridge. Plutarch and Kafka were his literary delicatessen.
His first-class education propelled him into one of London's top law firms. He rose through the ranks quickly, pulling longer and longer hours on a trajectory towards partnership. As he ascended he dropped reading books he loved, for legal documents written in the blandest of legalese. By the time Jerry arrived home in the evenings he couldn't bring himself to read another word. Vegetating in front of the TV with a bottle of Chablis were all he could muster.
His work had ruined his love of reading.
The same thing happens to writers. Nassim Taleb recommends serious writers get a sinecure, a job with little intellectual or writing requirements, that pays the bills, leaving them time to write, unencumbered by the need to make money from their writing. This leaves the writer to create pure work - rather than the overly edited and crassly marketed crap you pick up from airport gift shops.
I only remember what I choose to read.
In my work there are often technical documents or contracts that need to be read. This is a little like asking a dog to talk. I descend into a mental fog that would stop planes from landing. I read the words, but they don't go in.
Montaigne said "when I meet difficulties in my reading I do not bite my nails over them... what I do not see immediately, I see even less by persisting".
Reading is supposed to be a pleasurable experience. Void of effort, strain or (mental) fogginess.
If it's an effort, put the book down and read something else. The trick, as Montaigne said, is to be bored of the book, not reading.