1. Talking to people is not as easy as others say it is
Yes, I would like to make more friends, because having friends is great. No, I don't want to go up and talk to a group of people, let alone one single person. If I go up to talk to you, bear in mind that it took a lot of strategic planning on my part and revising in my head over and over of what I'm going to say, just so I don't stutter, misspeak, come off as some creep who just came up to you and started talking, etc.
2. Being in a relationship is scary and hard
Like I said before, talking to people is hard enough, but trying to talk to someone you are attracted to is a whole other journey. I, myself, am personally attracted to smarter women. If you're smarter than me and are a down-to-earth person, most likely I'll develop a 'crush' on you. That's kind of a bad thing for me because I'll spend days on end trying to figure out how to initiate a conversation with you, whether or not to text you about the homework, compare lecture notes, direct message you on Snapchat or Instagram, or just walk up to you and say "hi."
Keep in mind four out of the five options were over social media or text, because texting gives you more time to think about what you say before you say it, and you don't have to come up things on the fly if you would in a face-to-face conversation. Long story short, I'm single.
3. You like being alone, but don't like feeling lonely
I think everyone enjoys their alone time, some more-so than others, but that's common ground for us all. I really like being alone majority of the time. It gives me time to think about life, contemplate information better, and get a better understanding of my reality when I'm just alone in my thoughts. I DO NOT LIKE, however, feeling alone. I was a loner in high school, and it wasn't common for me to hang out with my friends outside of class. Getting to college gave me a new start, which is nice in some aspects, but not so nice because I have to start all over and make new friends again. Bottom line, being lonely sucks.
4. If you make friends who are extroverts, you don't have a lot in common
For the friends I do have that are extroverted, I can't relate to a lot of things they've experienced, but I do enjoy their company. I can't relate to crazy party experience they've had because, I don't go out much; I can't relate to your relationship troubles, because I've never been in one; discussing these topics it accounts for a lot of awkward silence in conversations.
5. Social events tire you out quickly
College is a big factor in this because there are so many social events that it really makes me have to think critically to which ones I think I have the energy for. I do really enjoy going to social events, but only if I have the energy for it. I'm pretty sure there's some science behind the reason why I get so tired after socializing and going to events, but I'm no psychologist.
My main goal in college is to step outside my comfort zone and try new things that would otherwise deter me, and I would encourage others to do so, but never will you hear me say that being introverted is a bad thing. Everyone is unique and special in their own ways, introverts and extroverts alike. At the end of the day, you should just do what makes you happy. If you want to party all night or stay inside all day, and if you want to push your boundaries, then go right ahead.