It is mostly likely physiological.
Bigger dick, needs more blood for same hardness.
I've seen and read that lots of bigger guys don't get fully hard, most the time.
Now, it is possible that he actually has something wrong with him. Or that you turned your old bf on more then you do the current. Or any number of other possible variables.
Ask him if this is normal for him. If this is, and has always been, his normal.
Well, the simple answer, is often the right one, don't overthink it or take it as a reflection on you.
I've dated several guys like that. Some are rock hard naturally and others aren't. As long as he still gets it "up" I'm pretty sure its not that he's not attracted to you. Tell him to get Viagra.. maybe that will help him get stiff
You definitely do not tell him to get viagra, unless he sees it as a problem and brings it up. That would be like us guys telling you gals to go buy some dieting pills because you're fat.
I have no trouble getting hard and since I've never used a condom my appendage remains rock hard throughout ;-) Maybe this guy does need to see a Doctor to find out if there's an underlying problem.
Ok yeah I understand what you mean but I wasn't saying it to insult him. I just thought that if every other option was exhausted then why not try viagra?
Depends on how turned on you are and how long you have been turned on also. If your super charged up you will be harder then normal. If the guys cock has been up and down all day because he is really turned on but doesn't want to masturbate... I call it making a super load... trying to build a larger size load of cum.. it can go either way... sometimes it is really hard.. but sometimes you start to tire out and your mind isn't into it as much so it is not quite as hard. but hard enough to do the job.
I know that this will differ man to man. It will even differ from time to time for the same man.
I've noticed that my penis will get harder when I masturbate sometimes versus other times. From personal experience, the more I'm turned on and craving that sexual release, the harder my penis will become. So basically, the hornier I am, the easier it is to become hard and stay hard.
I have no biological explanation for exactly how this happens. I simply have my personal experience.
Scroll Down to Read Other Opinions
What's Your Opinion? Sign Up Now!Bigger penis means it requires more concentrated blood flow in that area, Because there is more penis for the blood to circulate through it is therefore less hard? I don't know I'm just guessing here
Is normal, some guys need moer blood to keep the penis erect, in some p*rn movies you can see this guys with huge penis but they can even bend while they are erect, and yes, if you do some kegel Exercises you get harder erections.
you don't turn him on as much?
although mine is a little under the average it's hard as rock... am i on a good way>? LOL
It varies with the guy, and sometimes by situation with a particular guy. And you didn't say how old he is, but it gets a little more difficult the older we get.
Sexual Relationships 
Sexual Health 
Most Helpful Girls