This post is for men who have sex with women. 31F here.

Thinking about all the sexual partners you've had over the course of your life and the amount of time it takes you to cum from either oral or penetrative sex - is that amount of time pretty consistent from one partner to the next, or does it vary a lot?

For example: my ex would cum "quickly" from both oral and penetrative sex. Not 'premature' by any means, but faster than he would prefer, which was typically less than 5 minutes from oral and during penetration he'd need to switch positions after a minute or two, take a break, or switch between penetration and going down on me so he'd last longer. He always told me he never had this issue with any partner before me and could usually last for much longer, and it seemed to frustrate him. He never went into much detail about why this might be happening (and he may not have known), but would often say "I'm just so aroused by you" or something along those lines.

The discussion I'm interested in having here is what accounts for this variance from one partner to another based on your personal experience? Is it physical - e.g. more attracted to one person, better technique/feeling, etc? Or mental/emotional - e.g. concerns about performance, your feelings towards one person, etc? Or some combination of both?

Thanks in advance for engaging with this topic!

12/1 EDIT: (also posted as comment below)

Thank you to everyone who has responded to my post! I really appreciate your interest and detailed responses. I'm mainly interested in the differences and variety that exists for you from one woman to another, rather than within the context of one single partner. Most people responded with this in mind. I still think these are two different questions with two (mostly) unique sets of reasons, although there may be some overlap as a few suggested.

I'm really impressed with the wide range of responses, and I'd like to briefly summarize the most frequently mentioned reasons for why you may cum faster with one woman compared to a previous partner. In no particular order.

1. Enthusiasm; and adjacently - openness in terms of boundaries/kinks, willingness to communicate and learn, general inhibition, all of which feeds the sexual energy between partners. Some people have more of this than others, and many reported this affects how quickly they cum.
2. Anatomy - specifically the internal shape and feeling/texture of a woman's vagina. Some "fit" better than others depending on the size and shape of your dick. Like puzzle pieces. I find this to be particularly compelling because, for some reason, I never considered that my shape may be different than that of another woman. But I guess it makes sense. Also, physical size of the woman was mentioned (slim vs heavier) and this may affect the vagina's softness.
3. Attraction - many said their level of attraction to one woman over another can affect how quickly they cum. Their body shape, voice, or other physical features do something special and it's hard to last long.
4. Level of lubrication - some women get more wet than others.
5. Emotional connection - level of safety and comfort all affect you.
6. Lastly, technique.

As a follow-up question I'm now curious if the anatomy reasons like internal shape and texture can vary if you're wearing a condom or not?

Thanks again! This has all been very enlightening and I'll keep reading responses as they come in.