Edit: As expected. A lot of butthurt small dicked males in this thread hamstering worse than a female on the rag. Let's not accept reality, let's surround ourselves with "feel-good" bullshit (examples in comments: vaginal is not that important, women prefer clitoral, it's the size of the vagina that counts, top voted comment is a fucking woman who has no idea what she's talking about but caters to the general feels of the butthurt, etc. etc.). Welcome to the new TRP.

RP is about the truth regardless of how inconvenient that truth may be.

In that light, how important is dick size and what does it represent?

1) Confidence: Even at a young age, we are programmed to believe that a small dick is something to be laughed at and be ashamed of. We, as boys, make jokes on other boys in school/playground about having a small dick. We continue this trend for basically our entire life: tv shows making fun of dick sizes, articles, jokes and so on. This puts a lot of pressure on males with a smaller than average or average cock and makes them feel less of a man which, in turn, impacts their confidence levels when approaching or gaming females.

The other side of the coin is that males with a big dick get a passive confidence boost without having to lift a finger. Just knowing that you have a big package makes you more open to sexual encounters without any fear of being shamed, or, on the contrary knowing that she will be impressed by your size and girth.

If it were socially acceptable, I would be rocking with my majestic cock out even when going to the supermarket. And that's the confidence boost I'm talking about. The same way females with big breasts always show them off and use push-ups and revealing clothes.

2) Sexual performance: This is partly tied to confidence. Being confident in bed and taking charge, because you know you can satisfy her, as we know, is a big turn-on for females. Secondly, they are much more forgiving if you fuck-up or if you gave a shitty performance. Whatever hamsters say, getting rammed by a big dick for 3 minutes is more enjoyable than a 20 minute fuck with small shrimp.

How much of that pleasure is actual physical pleasure or just psychological is up to debate. On one side, the vagina's most sensitive points can be touched even with a 5 inch dick. So, in theory a small dick should perform just as well. However, in practice we know for a fact that they prefer a bigger cock and having heard that they like the sensation of being "filled up". So, in a sense, even if a small dick touches all the right places, a big dick makes her feel "filled up" which leads me to believe that it's actually just a psychological trick that gets her more aroused, and fortunately the brain is the most important sexual organ.

3) Evolution and alpha males: The actual question is: why do females prefer a bigger dick from an evolutionary standpoint? The same way they prefer a fit guy over a skinny guy is because of the protection he can offer and thus the tingles. In that sense, what evolutionary advantage does a big dick offer and why does it produce tingles?

I couldn't find any studies directly linking penis size to higher pregnancy, however, in the book Sperm Wars (fascinating book by the way) it talks about why the penis is shaped as a mushroom. Evolutionary speaking, a woman in a tribe was fucked by multiple males, and the mushroom shape of the penis has the ability to "flush out/ pull out" the sperm of other males increasing the chances of the last male to impregnate the female. If we correlate this to big penis size, we can assume that a bigger dick can more easily flush out deeper seeded sperm than a small dick and thus a big dick increases the chances of procreation with that particular male.

Because of that, maybe females are evolutionary attracted to bigger dicks regardless of the pleasure it offers. The same way they are involuntary attracted to alpha males who are not commitment material, even though a beta male, on paper, is a much better choice in long term survival in today's society.

Conclusion: Bigger dicks have a an advantage on the sexual marketplace regardless of what hamsters are saying in studies: "dick size doesn't matter" , "it's the motion of the ocean not the size of the boat" and other feel-good bullshit.

This is TRP and, as I said, we aim for the truth no matter how inconvenient that truth it.

Fortunately for those who won the genetic lottery and got a big cock have a win-win situation: confidence + a higher fuck-up margin + delivering more sexual pleasure = all combined create a vicious circle which only gets stronger.

Fortunately for those with average or smaller than average penises, the females can't see a man's dick until it's "too late". By that I mean that if she sees the male's penis she's already decided that she's going to fuck him regardless of his size. If we were to go out clubbing with our dicks out, that would be a different story.

In the end, dick size doesn't matter in getting her into bed, it only matters when trying to maintain a relationship (whichever that may be) with said female after the initial fucking.