I find answers such as &quot;my brain is getting slower as I age&quot; distasteful and unsatisfying. 
One can not do anything with an answer like that. On the other hand, a somewhat careful review of the process can lead in useful insights.
Reading between the lines in this article I notice a few points that I think are important to the cause of the author&#x27;s delayed progress at learning the game.<p>First the author describes how he set about reading all manner of strategies, variations of strategies, positions, tactics, etc. I think he shot himself in the foot with this. Humans tend to surrender when a task looks too daunting and his real goal was to keep up with a child who did not know anything about chess. None of the stuff he studied would be initially useful against a fellow novice with an innately short term focus.<p>Second, the author hired a coach, ostensibly to teach both him and his daughter, but later notes &quot;I would sometimes wander into the room when coach Simon was there, watching him present her with some puzzle on the board&quot;. 
So I have to wonder, what was he doing during the other occasions where his opponent was learning chess from an expert?<p>Third, the author&#x27;s stated motive to learn was to teach his daughter; he removed that motive when he hired the coach. Without motive to drive engagement learning anything becomes extremely difficult.<p>Finally, after he discovered the complexity of the learning task the author then set about studying all of the reasons why he could not do well at his initial goal. This, again, is not useful in actually learning chess.<p>All in all, it seems like the author actually learned a lot more than his daughter did in the same amount of time. However, his lack of focus lead him to spend the time learning many things that did not help him play chess at a novice level.