I have always loved to read, but my experience with technical books is more complicated than with other kinds of reading.
When I first started to code, I found reading programming books boring. It seemed like many of them were just repeating documentation.
I was mostly learning by practicing then: reading and writing code, googling and reading language documentation. I still read some books on software development every once a while, but I tended to choose the more "stable" and general-purpose ones, like "Code Complete", "The Mythical Man-Month" or "Joel on Software" (which are great). I thought that most of the books will get outdated soon, so I haven't read any books on the languages I used.
Several years and jobs passed, but I was still mostly learning by coding on the job, reading blog posts, and working on my pet projects.
Later, I had a very busy couple of years: maternity leave + part-time work, then full-time work + learning to drive. When I was able to return to a more steady schedule, I gained a great will to learn and fill blanks in my knowledge, but still hadn't much spare time to learn.
Around that time I stumbled upon a Sandi Metz's book "Practical Object-Oriented Design in Ruby". I decided that reading will be a nice way to complement my professional life. It took me a long time to finish the book (like 3 months :D), though it is really interesting. After reading POODR and doing some research I realized that actually there are many great books that don't get outdated instantaneously. Later I've built a habit and started reading much faster (which is a topic for another post I'm working on).
What I like about the books is: they provide structured knowledge. You don't need to search for the information on the topic each time. If you have a spare half an hour or even less, you can just return to the book and start reading. Over time you will notice how much knowledge you've got.
I found reading highly effective when accompanied by practice at work. It helped me to fill a lot of blanks in my knowledge and even gain more confidence. I would definitely advise my previous self to start reading tech books earlier in my career.
What about you? Do you see reading software development books as an effective way to learn?