I prefer the bottom to be bigger/taller/more muscular than the top

[jacques_roland]

I think most people (gay, straight, or otherwise) assume when they see a couple the shorter/smaller guy must be a bottom, and in general I've noticed most men assume smaller stature guys are bottoms.  For awhile I used to hold a similar view point but over time I've actually come to the opposite preference!  

I prefer it when the larger/bigger/taller/more muscular guy is bottom :]

To be clear, I'm quite versatile (best partners are where we switch roles almost every time) and don't really associate to any role (top, bottom).  In fact I hate the forced dichotomy which seems like a lot of people still follow based on my experience on Grindr and Tinder.  

But I find it much hotter if the bigger guy bottoms:

1.  Being inside/topping someone makes me feel very secure with them, it almost feels like I'm just cuddling them as close as physically possible.  It feels like they are protected me.  So it feels amazing when the bottom is someone stronger and taller than me.  
2.  It's a great reversal of expectations (which makes things hot because it's unexpected/taboo).  I've seen porn and sigh because 99% of the time the bottom is the small/twink guy and the top is the muscular guy--incredibly boring.  Hottest scenes involve the smaller/twink guy topping the muscular jock :].
3.  Bottoming can sometimes be hard on the body and I think takes a lot more practice/skill to get comfortable with it.  So when a bigger guy goes out of his way to bottom, it feels like he's showing he cares/loves me a lot.  
4.  I think it's kind of gross there's all these men who assume little twink guys just want to bottom for them.  
5.  Finally, it feels like it's straightness being forced onto gay people.  In most straight couples the girl is much smaller than the guy.  Feels very unoriginal and unimaginative to just assume it carries over.  

Anyway I think most people would strongly disagree (and Porn says so as well, but it's okay real life is always more exciting than the fake stuff), and a lot of these preferences are developed over many years of experience and experimenting, so there's no real wrong preference I think.  But the real message is people should not assume just because a guy is small he must prefer bottoming, or if a guy is tall and muscular he only wants to top.

[InbetweenDreams]

Hmm, I don't have expectations on guys. In other words I don't assume that a guy is a top or bottom, dominant or submissive. It is a common stereotype but I'm not that naive, that would be silly to assume that one guy is submissive or is a bottom because of their stature.

That being said, I am one of those guys who likes shorter, smaller guys and I am a top, so yeah...that's just my preference. I don't think there's anything wrong regardless as long as people are happy.

I also had really terrible experiences trying to bottom. In my early days of coming out and dating guys one them was too impatient and was extremely painful then insulted me. So, yeah a bit of anxiety when I finally do get somewhere with a guy that one way or another I'm going to be a disappointment. I'm all for trying things and I would try to bottom for someone but I really have to trust them.

I guess straight people and probably younger guys assume roles visually. Then again a lot of stereotypes work that way too.

I like being the big spoon, to be the "protector" sort to speak...but emotionally I feel like I would be the "little spoon" if that makes sense. I have to feel secure in a relationship. My ex didn't give me that sense of security. I don't like the feeling that at any moment my partner is going to kick me to the curb.

As long as both people are happy. That being said, let the haters hate, sometimes you can't fix stupid. Err well you can't fix stupid, stupid people don't know they're stupid.

[eastofeden]

Over the years in general I have noticed that shorter guys tend to be "tops" and tall ones tend to be "bottoms" quite frequently. Two of my closest friends for years were both very short - maybe 5' 5"/5' 6" and they used to complain alot about taller people assuming they were bottoms. They had some great stories - used to make me LMAO.

You are probably correct about the straight comparisons - for alot of people images are everything but often have nothing in common with reality.