For me, it's the overall driving experience, the Golf platform makes every drive feel special and fun, even if it's just to the corner store to pick up a gallon of milk and a few necessities.
It's the solidity of build, that solid thump when closing the door, the perfectly weighted steering, that great dialed-in handling, it's got that feling of precision and composure that other cars in it's price range are simply lacking
it's the most driver-focused car in it's price range, sure you can spend more on more "glamorous" nameplates, but you're really just paying for name and exclusivity
I know they're nowhere near in the same class, but the first German car I ever rode in was a friend's father's Porsche 911, a early '80s model with the "frog" headlights, it was a 911 Carrera with the whaletail spoiler, when we pulled onto the road, and were squashed back in the seat by the torque-heavy acceleration, I was hooked!, when we carved a couple corners and it handled like it was on rails, I was utterly obsessed with that wonderful car, I still consider a classic '80s 911 as one of my "Bucket List" cars, one of the true 911's with the engine and drive wheels in the back, where they should be, none of that silly front engine/AWD abomination that the current "911" is
the first time I got in my '07 Rabbit with the 5 speed manual, it felt like I was in a baby/slightly detuned '80s 911, it may not have had the power and torque of the 911, but the handling felt remarkably similar, my current daily driver '12 Golf TDI feels even crisper than the Rabbit, probably due to the low profile 45 series tires...
for me, it's the total package, VW just gets it *RIGHT*, the cars are extremely fun to drive, make each drive an event, and do it at a price point that most drivers can afford, especially if you buy used
every time I get in my VW, whether it's the Rabbit or the Golf TDI, it puts an ear to ear grin on my face
anyone who rides in the car(s), especially if they've never been in a VW before, remarks on how comfortable they are, how nicely they ride, and are generally surprised by the performance and handling, they're a definite sleeper.
Mom has been using my Rabbit as a backup car for a while now, and she raves about it each time, it's a refreshing break from her stodgy, mundane, lifeless '14 Honda CR-V automatic
she's even said that if she didn't like her Honda so much, she'd genuinely consider a Golf/SportWagen TDI, but as her CR-V is paid off, and reliable, there's no *logical* reason for her to trade out of it, she'd be trading a vehicle she *knows* for an unknown variable of a new-to-her car.
besides, whenever she wants to have an enjoyable drive, she can just hop into the Rabbit for a few Smiles Per Gallon...