When my son was playing baseball competitively, he watched baseball all the time*. He was a very good player and played many different positions, eventually settling down to second base. Watching games was hugely instructive - the game is too complex to completely teach on the practice field.
Now that my daughter has fully embraced soccer and has found a home at right outside defender (right full back), I've picked up a couple of instructional videos on the topic to help her learn the position. I just watched two to get the gist of them.
Like baseball, the game is way too elaborate for any coach to teach in team practices. After two years of rec, four years of club and one year of high school ball, I learned all kinds of new things. It's not just games that we need to watch, you really want to give yourself an intellectual foundation with instructional videos before watching the games. It's like learning the vocabulary and grammar of a language before jumping into watching movies in that tongue.
Way back when, I was her motivating factor. I told her she had to pick a hobby and she had to get good at it. She chose soccer, but I had to make her practice. In the last two months, her internal motivation has kicked in and I regularly get texts from her after school letting me know she's heading for the handball courts to work out. It's awesome.
Now if I can just get her to watch more TV, she'll become the best full back in the league.
* - This is in contrast to his behavior now where he watches baseball as much as is humanly possible.