Zillions of barriers.
Lack of social skills prevented me from making friends most of my life; they can be so terribly bad, even to the point of me saying something inappropriate without even realizing it. People always have to be direct with me, NEVER passive - otherwise I'm very unlikely to understand what's going on.
Lack of common sense prevents me from doing my job as well as I should and that brings about lots of very awkward moment with my boss and coworkers. It also makes me say and do a lot of silly things that lead to very awkward and embarrassing situations with NT's. It also causes me to make so many obvious mistakes at work without even realizing it unless I'm told, and that ends up leading to another barrier I'll be describing here (very low self esteem).
Being unable to control my emotions makes me not be as good a son as I should be, and I've written very long rants about that on here. It makes me lash out verbally at my parents whenever I'm in a bad mood, and the smallest thing can trigger it. Even if I lash out at myself, it totally drives them nuts - all the childish tantrums, and never being able to stop them. The meltdowns are the worse, they can get as bad as me punching myself in the face. It makes my parents (and honestly, myself) really worried about my mental health.
Being afraid of so many things makes me limit myself on what I do in life. I never learned how to swim because I'm afraid of drowning and pool germs. Being afraid of insects and bats makes me not go camping, and people were shocked to hear that I've never gone camping. Being afraid of driving (stemming from my fear of death combined with hit & run OCD) makes me stay home much of the time or otherwise ask other people to drive me places (like Sheldon Cooper from TBBT) or waste money on a cab. When I actually drive myself, I never go anywhere far. Being afraid of raw meat germs and getting burned and/or cut prevented me from learning how to cook. The fact that I limit myself so far actually makes me boring. I'm also literally afraid of people's reactions, so it pretty much makes me afraid of people - in a way. Many of my specific fears are actually stemming from one huge general fear - death. I fear germs because they might cause a potentially deadly infection. I fear driving because of deadly accidents. I fear bats because of deadly rabies. I'm afraid of drowning because drowning leads to death. As for insects, I mostly fear them because they're creepy and their stings can be very painful (low tolerance to pain, another fear).
Always worrying about things limits me in terms of how happy I can be. The continuous anxieties about the uncertain future, as well as regrets about past situations, simply make me miss out on half of life. This actually leads to a new regret, over what these anxieties made me miss out on. A never-ending vicious cycle. The anxieties also make me under-perform at work because all these intrusive thoughts are capable of clouding my mind, therefore prevent me from concentrating on the tasks at hand and thus prone to making more mistakes.
Speaking of cycles - being unable to ever let go of things makes me constantly cycle over the same topics and that really pushes people's buttons, at home and at work - often to the point of them screaming at me and really hurting my feelings and self-esteem.
Speaking of which, having extremely low-self esteem makes me limit myself in how I function in this world. I feel like I'm bad at so many things and it might be one of the reasons I under-perform at work (and in life). It makes me more prone to mistakes and it makes me more likely to throw childish tantrums. I'm also extremely afraid of making mistakes and disappointing people, and that ironically can lead to those same feared mistakes. The self-hatred can really throw me into depression and thus make me under-perform even more. This self-hatred has ruined my relationships with people, and in turn, led to even more self-hatred; another never-ending vicious cycle. Low self-esteem (even when it doesn't reach the point of self-hatred) also made me miss out on things like chess and judo; I was bullied in judo (taking judo wasn't my decision, but my parents' suggestion) and ended up quitting. I never joined the chess club because I assumed everyone was so much better than me.
Lack of motivation makes me more prone to being distracted, as well as under-perform in life and miss out on a lot of opportunities - just like with the fears. I think it might be one of the main reasons why I'm bored a lot (the others being anxieties and loneliness that results from poor social skills). I don't know, I just don't have any ambitions in life and this makes me feel that I don't really contribute to anything. It's also the reason why I keep abandoning any books that I start reading; I never really enjoyed reading, but lack of motivation makes me simply not stay focused on whatever I start reading. There have been so many other personal projects that I made an attempt to start but then dropped. Combine this with anxieties, and I'm just a useless lump. When I don't work, I mostly just sit at my computer playing games, watching YouTube, browsing Google Earth, listening to online radio, and being active on AC (in terms of AC, I'm actually super-motivated. I love this site and all the people on it!!) This is also why I haven't been taking AP classes in high school and not participating in extracurricular activities (I've only joined a couple of clubs and just took AP Spanish because I'm good with languages); I could have been a valedictorian and I missed out on a golden opportunity (here comes the regret again).
Being a picky eater prevents me from having an optimal diet. I tend to eat mostly meat, and I don't eat full meals - like I might eat a few chicken legs alone, and then I might follow it up with a tomato. I refuse to eat certain types of foods even if my mother offers it, and I never eat store-brand foods. I don't eat a lot of fruits and veggies (I do love tomatoes, though) - so mostly just meats, junk food and desserts (without any nuts, but that's because I'm allergic to some types).
So - after having done tons of research and having done some sessions with my psychologist, I conclude that these barriers are in fact related to my AS simply because I have AS. I know many of these qualities can pertain to NT's as well, but due to the fact that I simply have AS and these qualities happen to be common in AS, it leads me to conclude that in my personal case they do in fact pertain to my own AS. All these barriers simply prevent me from living life to the fullest. I feel like I've only lived less than 25% of what I could have. Ironically, my worst fear (death) is one of the main factors behind it all as I have described in the paragraph about fears.