Of Rory Gilmore's three big loves in Gilmore Girls, Dean was the first... and some fans might even say the best. The two met at the start of the very first season and quickly got together - and with only one short sort-of-breakup in the middle, they stayed together for two years, a lifetime for a teenager! They were great together, too, and stuck it out till Rory fell for Jess.
Eventually, these two did have an affair - not either's finest moment, and Dean ended up married to someone else, while Rory ended up the revival with the shocking reveal that she was pregnant! Should she have stayed with Dean all along, or did she make the right choice to leave him as a teenager?
Perfect For: The Best First Boyfriend
As Lorelai pointed out, Dean was the best first boyfriend that a girl could want. He was sweet, and loving, and treated her extremely well, and that's a kind of history that can't be underestimated. If they stayed together, Rory would only ever have been with someone who treated her right, and they would have had an incredible story of their first meeting and early relationship to tell the grandkids. It may be rare for a couple to stick it out from high school, but when that happens, it's incredible.
Not Perfect: Married To Other People
Ah, so much cheating. Dean and Rory may have been great when they were first together, but after that, things turned toxic. She and Dean cheated on his wife, and that's a difficult thing to get past. If they had got back together after that, trust would be a difficult thing to build.
While both were at fault here, it's a problem - and of course, in the revival, Dean isn't even an option, as he's remarried (and is seemingly much happier about it!).
Perfect For: Gets Along With Her Family
Having a partner that gets along with the family is a big deal, and Dean definitely came with the Lorelai Gilmore stamp of approval. She liked him for himself, and for how he treated Rory (and for his skill at changing the water bottles...). Even Rory's grandparents met and approved of Dean, and while it's important not to make decisions about a partner based on what other people think, it was definitely a point in his favor.
Not Perfect: She Cheated On Him
Dean wasn't the only one of this pair who was a bit of a cheater! When they were first together, Rory cheated on Dean, too. First it was a kiss with Jess at Sookie's wedding, but this was exacerbated by the fact that she was essentially emotionally 'cheating' on him for the entire end of their relationship. He knew it, too, which is why he finally ended things. It's a hard thing to recover from, especially knowing that Dean just couldn't keep her attention.
Perfect For: She Gets Along With His Family
As well as Dean getting along with the Gilmores, Rory got along with Dean's family, too. We didn't see a whole lot of his parents, but his little sister, Clara, was a big fan, and Rory was clearly on the approved list for him, too. Once again, there are more important things, but this would have been a combining of families that worked for everyone - something that was impossible with both Jess and Logan, Rory's next two big loves.
Not Perfect: They Want Different Futures
This is probably the bigger reason that the two would never have worked, even if Jess had never come to town. At the end of the day, these two just want very different things. Rory wants adventure, travel, exploration, and a major career. Dean, meanwhile, wants to settle down - he wants a career, he wants kids, and he wants a more traditional life overall. At the end of the day, their futures just don't match up!
Perfect For: He Understands Stars Hollow
Dean may not have lived his whole life in Stars Hollow like Rory has, but he has lived there since he was a teen, and he understands the town and how she fits into it.
Unlike Jess, who couldn't wait to get out, or Logan, who would never understand that kind of upbringing, Dean just gets it - and for someone as attached to her home as Rory, that goes a long way to making the perfect partner.
Not Perfect: He Doesn't Read
He knows how to read, of course, but Dean just isn't a bookworm. Unlike Logan and Jess, he was never the guy that could really meet her on an intellectual level, and that's something that would definitely cause issues for the two of them in a long term relationship. Rory is the ultimate bookworm, and she absolutely needs someone who can talk books with her, not someone who will just stand by and find her reading habit nice.
Perfect For: Would Do Anything For Her
Dean was always willing to do just about anything for Rory - and that's an amazing quality to have that would go a long way to making things work in the long run. Dean went to the debutante ball for her, even though he thought it was ridiculous. He met her grandparents, he hung out with her mom, he went along with their traditions and TV nights and wild eating habits, and he was always there to accompany her to everything that she wanted to do.
Not Perfect: He Doesn't Challenge Her
The flipside to the point above is that Dean never challenged her. He was always just happy to go along with things, and it quickly became clear after him that Rory wanted someone who was going to be more than just a pushover. She wants a man who can challenge her intellectually, and that she has more of a spark with - someone to help her evolve, not just happily sit by her side... and Dean was never going to be that.