Often I have very little desire to have to ask Liz, my fiance, for what I want; I just wish she knew. If you ask me about this, I'll respond in the same way most people do "Of course I know that fairy tale romance is bullshit and you have to be clear and communicate about your needs and desires." However, when I have to be the one communicating, I often take a much more passive approach in real time than I tend to give myself credit for. I notice a lot of people do this same thing.
Even now, when we have evolved so far to accept and create all types of different relationship forms, we still think magically in many romantic circumstances.
"When it's right, you just know." Yes, this is true, but no way other than intuition exists to make a decision with so many variables--i.e. picking the right partner. Maybe it's a mystical force inside us, or maybe it just feels more right than anything else has.
"Fighting is healthy!" Yes, it's also true that if you're relationship doesn't experience conflict then you're likely not engaging with each other, but a lot of intense argument doesn't indicate in itself that a relationship is good, and the fact that fighting is healthy does not make violent communication acceptable.
In the case of asking for what we need, almost none of us would say out loud that we believe our partner should know what we want without having to say it, but in practice, like I did and do with Liz, I've seen almost no people that follow this guideline in real time.
The result is not hard to imagine, one or both partners do not get what they want out of the relationship and this causes pain. In response, one or both partners take passive-aggressive strategies to get those unmet needs met--kind of like a last ditch effort at maintaining the idea that these things can magically happen. For example, you don't ask your partner to split house chores with you and publicly mock him or her for being lazy. This leads to resentment, which in turn moves a relationship toward break up.
We, as modern folks, intellectually understand this issue. Yet, in response, we cite the idea that having to ask for what we want makes the action less special than it would be if our partners just knew what to do. Or, even more common and faux-practical, if we ask for something and then our partner does it, we have to be suspicious that it's not genuine and they are just doing it to be conciliatory. If we buy into these two ideas, it leaves us with no good options.
To me, however, the fact that Liz is willing to take my requests into account and perform some of those actions to make me happy and meet my needs (as long as it isn't harmful to either one of us, of course) is one of the most special things I could imagine. This coming to the middle for the sake of your partner's well-being is one of the greatest gifts that can be given in romance. Yes, we shouldn't just ask for a bunch of shit and expect our partner to change, nor should we simply pander to any ridiculous request made by him or her, but the process of meeting in the middle through communication is when both partners feel the best and the relationship thrives.
To recap, if I don't ask for what I need, it's very unlikely I'll get it. That desire probably won't fade and if I stay in my relationship I'll just start to feel contemptuous toward my partner. As a result, I'll say something mean to her and she'll then start to feel angry or sad or some variation. Then she'll feel like her needs aren't getting met, which will make it more likely that my needs will get even less met, and the cycle continues.
All of this can be unraveled by simply stating what you need, and requesting your partner to do the same. Maybe a Disney movie won't be made about your life, but I promise you if you work hard enough at communicating in your relationship it will get to the point where it feels magical but is rooted in complete practicality with a little mystery on the side.