Nice topic.
I just thought about one thing the other day.. I was collecting mostly Batman figures when I was a kid, always would ask my mom a Batman figure for my birthday and christmas. There was also a time when I would only want Star Wars figures.
Now with aging, I've had different collections of stuff, all of which I quit and sold. There was even a point when I would only collect vinyls, cd's, cassette tapes from a specific rock band (don't want to mention who here). This particular collection drove me nuts, because the more I kept collecting those vinyls & stuff, the more I ended up finding rarer and rarer and rarer stuff. I began buying $5 stuff, and at some point I would buy $500-$1000 stuff. I stopped when I was about to bid on a $10000 cassette tape (extremely rare, only one unique copy recorded by the band I was collecting the most) and realized it would never stop, there would always be a new thing to buy at a crazy price.
The craziest thing is that I would almost NEVER watch those stuff. I just knew I had them and had one of the most unique collections on the planet, I had 3 rivals on that collection. It was insane. I realized I wasn't collecting those because I loved the objects, but just to feel unique. It gives you a weird sensation of power, it's very abstract to describe. Like you're one of the very few people to have a specific item. In the end, I understood that the only important thing for me was the music, so I sold most stuff to one of my rivals (which pretended to be my friend, but after I sold him what he wanted, he vanished from my life. Sometimes I wonder how crazy he got haha).
There was another moment, later... when I had almost nothing in my home, no object, no figure, nothing. Like Tyler would say in that movie Fight Club: what you own end up owning you. I believed in that statement for a long time, and to some extent it's true. You're not owning anything for real. It can break, it can get stolen, and anyway you look at it, you won't bring them in your grave, nor will it give you anything special.
Now I've matured a bit, got older.. I don't care about the money it costs, I don't feel unique about having anything, I just care for the beauty of it, just like I care from staring to my girlfriends' eyes thinking: she is fkin beautiful. It's just a moment of pleasure. If you like a figure, it's a moment of pleasure, you look at it, and for an instant, you forget everything else, you just look at the figures, the beauty of it, the memories it gives you, the little moments you love in the movie or series it's originated from, and that's it. It's as enjoyable as eating a fine meal or anything else. It's just a moment.
So I don't see myself quitting Hot Toys, because I just buy what I really love from them. And to me they're the best toy company ever, the quality is there, I have almost nothing to complain about.
I'm not a completionist, I'm just buying all the figures I love, no matter the money. I know that IF I part with them, I will make my money back. And the money I put into it, I know that I have enough money to do anything else I enjoy in life and to make my girl happy, so it doesn't matter as much as when I was younger. If I was in the red, I would have no problem selling everything. If I get stolen, never mind, **** happens. It's not like losing a limb or someone you love, it's nothing really. Just plastic, materials.. nothing really important. But it's beautiful nonetheless. I'll just remember the good moments of staring at those great figures when it's all over.
When you feel the need to stop or quit: just do it. Sometimes you get bored, sometimes you wonder what you could've done if you spent the time and money on something else, and those are good questions. Just follow your heart and what you feel you need.
In any case, don't regret it, it's lots of memories no matter what. You also meet some people, sometimes it's worth it, sometimes not. I still have nice memories of my crazy vinyls/cd/cassette collection, it was insane and fun.
Oh and back to what I was saying at the beginning, I would only collect Batman figures when I was a kid. Funny to see I still collect (much more expensive and well made) Batman figures in 2016, ahah. Guess it's what I really love.