I never collected just for the possibility of a book growing in value. I was all about the stories. However, there were a few books I bought multiples of just on the chance they would go up in value. After the speculator crash in the mid to late 90's, I gave up on that. Now, I usually will just grab a trade.
It's maddening now. There's an app at the center of the speculation business now. A rumor of a TV show/movie/whatever, it's posting and telling folks to get this book or that book. And people subscribe to it. They live by it.
Sun and I (at least I think it's our Sun) are a part of this comic collectors Discord server where some live by that app. The focus is off of the Big 2 these days (unless there's some announcement) and are keying in on the indie titles now since the do lower print runs.
Case in point, I have been following the series Black by Kwanza Osajyefo. It's its own universe in which only black people have super powers. Well this latest series was announced, titled White, and it was announced to have a print run of only 2,500 copies each issue. The app went crazy with speculation. There was a total of over 40,000 requests for the first issue. I eventually went digital with the series. The first issue (first printing) was at $150 at cons late last year. It was at FanExpo Dallas for $30. I can't explain how it (speculation) hasn't crashed more.