1. Your circulation slowly getting cut off until it's too late. Pinching a nerve and feeling pins and needles throughout your body is never as bad as it is during a cuddling session. It's like the old adage about a frog in boiling water: your arm is slowly crushed under the weight of snuggles from your significant other. Eventually, the snuggle pressure per inch (SPPI) is too much to handle, but by then it's too late. You wake up from a nice doze thinking your arm is on fire.
2. Having hair. When you're tangling up your bodies like a love-pretzel, it's unavoidable that your hair is going to get pinched underneath your partner's arm or caught in your jewelry. Few things ruin a good cuddle session quite like almost getting scalped by a watch.
3. The potentially relationship-ending struggle to regulate your wildly different body temperatures. It's impossible to settle on just how much space you need when one of you needs to share body heat just to survive and the other is sweating like they have malaria.
4. Feeling like you're inside a giant wind tunnel that smells like a mouth. Getting breathed on can change things so quickly. It's so subtle, and yet so unpleasantly distracting.
5. Being uncomfortable, but knowing your partner is really enjoying things, and if you move, you'll disappoint them, and you can't let them down. They look so cute when they're sleeping. If you interrupt them now, you're a monster.
6. Getting stabbed by scruff. If your cuddling partner is a dude, and that dude has gone through puberty, then your cuddling experience is not unlike that of hugging a porcupine with a beard or rubbing sandpaper on your face vigorously while dry-humping a body pillow.
7. Everyone has a good snuggle side (and a bad one). If you're one of those people who sleeps on their side, you definitely have a preference as to which side you fall asleep on. The idea of an impromptu cuddling session that winds up with you on the wrong cuddle side fills you with dread.
8. Being the big spoon. Let's not mince words here: the big spoon gets cheated out of the premier cuddling experience. Getting bumped to the outside by a dude that wants to "feel safe" can probably feel pretty awful (but also, we need it sometimes, ok?).
9. Boners. It doesn't matter if you have one, your cuddle buddy has one, or you both get one. Boners ruin the cuddling experience and force you to make an important decision: You're either done cuddling, or you're having sex (and even then, you're still done cuddling).
10. The horrible sensation of your worst body parts making contact, also known as "footsie." Lots of people hate feet, and if your feet have to touch other people's feet, it's like having to poke a snake with your feet. Feet touching is inevitable when your bodies are intertwined, but that doesn't make you any less prepared for having someone's toenails scratch your ankle.
11. Having your upholstery torture you. If you've ever gotten your cuddle on atop a tiny love seat, you know the pain of overextending your topmost vertebrae all too well.
12. Trying to correct the inequality of pillow real estate. If your partner-in-snuggles monopolizes the pillows, you're stuck making do with the mattress or the fat and bone wrapped in skin they call a body. Neither of which is as comfortable as one of the pillows your partner's hogging.
13. The advanced yoga move known as watching television while cuddling. Good luck straining your neck muscles constantly so you can peer over the mound of human being you're hugging just to make out what's going on during Bachelor in Paradise.
14. Squished arm syndrome. Almost every available cuddling position forces you to fold your one arm under your body in the most uncomfortable way possible.
15. Disproportionate shoulder to head ratios. If you're trying to pull off the seated cuddle, it's impossible if your boyfriend's shoulder isn't the perfect height for your resting head.
16. Cuddling a human body. Human bodies were not meant to be cuddled. They were meant to act as husks for our brains to control until they give up living.
17. Not being able to cuddle right now. For all the problems cuddling can cause, it's still the (second) best way to spend time with someone.