After reading exhaustive amounts of articles and book chapters on coin collecting basics, what to look for, and how to be a "successful" collector, I have reached probably the most unpopular opinion in all of numismatics. According to most everything I've read, you're only a successful collector if you turn your collection over for profit. And to me, that makes you a dealer, not a collector.
Now don't get me wrong, I don't have any problem with collectors that buy and turn to make money to buy the next thing, but why does that have to be the benchmark for what makes you 'successful'? Can't buying what you like, regardless of potential financial gains, be considered successful?
If you've been hunting for a particular coin for a long time and you finally find one, that's a positive result. Positive results to me equal success. Starting at your new purchase and then poring over sales records for the next several years to track margins over your purchase price sounds like a job, not a hobby. Like I said from the start, unpopular opinion.
Think back to when you first started collecting things as a kid. Not necessarily coins, but if you started young, good for you. I mean collecting things because you thought they looked cool. I knew kids that collected bottle caps, buttons - the sew-on-your-clothes kind, rocks, bugs, the list goes on and on. Was that for profit, or because you enjoyed it? Just because we're all grown up doesn't automatically mean we have to be motivated by money. My grandfather was a lifelong mechanic, and he collected Studebaker cars/parts to build a completed car off his own. He didn't do it to try and sell it, he was motivated by his love of the car.
I collect coins because I enjoy looking at them, learning about them, and sharing them on social media platforms. I collect for the artwork struck on the surfaces and because I enjoy history. I like to learn about the person(s) on the coin, what was happening in the country at the time it was struck. If there are animals or designs present, what, if anything, do they represent?  Obviously from those descriptions, I collect coins from all over the world, and I do it for the variety. I collect for the love of the coins, not for any profit I could raise from selling them. Believe me, there isn't a lot of profit to be made unless there is some precious metal content and they can be sold for melt. (Just as an aside, I also am slowly building a "no gold" US type set, and I love Peace Dollars.)
I consider myself a successful collector because I collect what I like, and I learn about what I collect. Each purchase still feels like an accomplishment. I see a coin that looks attractive in design and I purchase it. I don't worry what they've sold for in the past, and I don't worry what I might be able to sell it for in the future. I enjoy my collection in the now - now is when I'm collecting, now is when I'm learning, now is when I'm sharing knowledge and images with others. That to me is success.
Anyone that my end up reading this will probably think, 'you're a novice collector', 'you're naive to what the hobby is about', or 'you're just a world coin collector'. And that's part of the problem with adding new collectors to the hobby; the, for lack of a better term, snobbishness of "serious" collectors that have been doing this for years. I personally don't belong to a coin club because I feel like I would be ridiculed for what I enjoy collecting. I was bullied enough growing up, I would hope at 40 years old, I could get beyond that. Maybe I could end up being the group's world coin guy, but maybe the derision of not focusing solely on US coins for profit because I live in the US would drive me out first.
I went to my first ever coin show a couple weeks ago in Austin, Texas. It was a small show, but I enjoyed the experience. Unfortunately for me, I had one dealer that treated me as if I had spent to much time in his chair because I was looking at world silver, and as I sat back to check my phone for values on a coin I was considering, he said "thanks for coming by" as a way of chasing me off. I was looking at coins (not bullion) that he had listed at higher prices that some of his US items. The show was saved for me though, by another dealer from San Antonio, ANA Life member 6463 Patrick O'Connor. We had a nice conversation about pieces I was looking at on his table, and I made a couple purchases from him and his wife. All-in-all I guess it was a successful trip for my first show, but I was still left with a sour taste from that one interaction.
Am I a successful collector? I believe I am. I am able to find what I like, buy it, learn about it, and enjoy the time I've spent. I post photos for others to see and I share some of the knowledge I've learned along the way. I encourage other people to collect what they like, not just what will make them money. Am I a dealer? No. I haven't ever sold any of my collection. To me that's the big difference. The popular opinion is that to be considered a successful collector, you have to be able to transition into being a dealer and sell your collection. I didn't get into this hobby to be a dealer, to worry about making a profit. I got into it to collect information, and the coins are vessels for learning that information. I collect because I love coins. I collect because I love the art they contain and the information they unlock. I collect because I love to. It may be the unpopular reason, I may be labeled unsuccessful or naive or even 'just' a world collector, but the knowledge and enjoyment I gain make me successful in my own right.