I’ve been wanting to collect Koffings, Weezings, and Galarian Weezings (KWGW) for a while, but never really got started until this year. I have always liked poison types (poison and steel are my favorite) and have some nostalgia for KWGW. Shiny Koffing has been my pfp for my entire time on efour as well. I think a major motivator for continuing to collect KWGW is that most of the cards are pretty cheap and easy to find (at least for English which is my primary goal). My goals have changed some since starting. For instance, I am collecting all the base set Koffings. I may branch out more into errors and nontraditional cards, of which Koffing and Weezing both have a few. I have some other species collections that are slowly growing as well, but nothing to the level of KWGW.
Having a place like efour or the species collecting discord are also motivators. I made my first species post recently and was happy to see positive responses and lots of interest.
Before one gets started, I would research your favorite pokemon on pkmncards and bulbapedia to get an idea for whats out there. I’d also heavily recommend doing daily ebay searches for your favorite pokemon. I have found great deals and lots of new and cool cards that way. Also, dont let someone else dictate how to collect. Thats just good advice in general really