Top Tier:
The top tier are those that have dating fairly easy; they're the chads, the stacys, the young attractive women, the tall good looking successful men, etc... Finding a partner is fairly easy for people in this category and they typically have many romantic or sex partners during their lifetime, especially if they choose to live a promiscuous lifestyle. Those in this category can find hookups or one night stands without much difficulty and would be successful in an environment such as Tinder or the bar where looks are paramount to your success. Many in the top tier rarely get rejected and when they do, it doesn't phase them since they can find someone else fairly quickly. I would estimate that the top 10% of men and the top 25% of women fall into this category. More women fall into the top tier because dating in general is easier for them, especially if they're young and attractive. However with age, many eventually fall off of the top tier.
Middle or Normie Tier:
The middle or normie tier are the normal people with normal level difficulty when it comes to dating. Dating isn't easy but it isn't super hard either. Unlike the top tier, those in this category typically have to work to be successful in dating and can usually eventually find success, even if it's not as frequent as those in the top tier. Most have their first partner and lose their virginity at a relatively typical age (16-21) and many go on to have a couple partners throughout their lifetime. For men in the normie tier, they can occasionally find a one night stand from a bar or a hookup from online dating if they're lucky, but not as frequent as those in the top tier. I would say 80% of men and 70% of women fall into the middle or normie tier.
Bottom Tier:
Finally, the third and bottom tier are those that have dating on hard mode and have it harder than the average person. Most people in the bottom tier have a series of negative flaws which makes dating harder than average, sometimes even significantly harder than average. Those in the bottom tier are much more likely to wind up virgins at older ages or remain celibate for a long time. Many men in this tier become incels or misogynistic due to repeated failures with women. However, some get lucky and manage to escape and go on to have a meaningful relationship, although most in this category will likely never be successful in the hookup/one night stand department. The majority of incels, foreveraloners, and 25+ virgins by circumstances fall into this category. I would estimate that the bottom 10% of men and the bottom 5% women fall into this category.