I read. A lot.
Most writers tend to. For many, reading the works of others becomes more than an escape, diversion or pleasure trip. It becomes a study in the craft of writing. A process of learning by observing, then followed by doing. Nothing wrong with that approach.
I find remarkable not just what I learn from reading other works, but how I learn it. Sure if there are outright errors or grammar inconsistencies, I can't help but spot them and wonder how they got overlooked. Logic and plot problems tend to jump out at me too. Bad characterizations, factual mistakes, poor choice of wording, all of this becomes a lesson is what not to do. What to beware of.
When it comes to the positives, the things other writers do well, I seem to have two methods of learning. I think of those two ways as active and passive.
The active method is where I consciously pick up on what the writer is doing. In this case I tend to be more a student and learner than a casual reader. Which makes it a great way to absorb techniques, practices and skills but at the cost of really investing in and enjoying the story. Again, nothing really wrong with that. Though it can be frustrating at times if all I wanted was a good read, not a writing lesson.
I think the passive method of learning is, in the end, the more powerful and compelling of the two. The difference here is that I rarely find myself not being a casual reader. I let the story carry me from start to finish and just appreciate the journey. Only after I turn the final page do I really reflect on how the story was written. Quite often I'm amazed at the deft skills the writer exhibited. I find it thrilling to reflect on how they brought the story to life first. Afterward, I consider the methods, styles and tactics they used to execute the story to such great effect.
I suppose it comes down to experiencing a well written story versus an engrossing story that's written well. What writer wants to settle for just delivering the former?