When I orgasm from fellatio alone, it's usually only by one partner who makes sex into an all day session, with coffee breaks. The technique is not aggressive to make me have one, as it's each sex partner's artful process. Guys who want to hurry it up and cum deliberately are looked down upon, because then once it happens, what's really left afterwards.
Some sex partners who are determined to make me have an orgasm generally can't do it from fellatio alone. The hand and cream or oil are introduced at some point to finish me off. usually the result of their mouths getting tired.
For me, it's not important to ejaculate, and I don't care whether or not I do. Which is good because often I don't. I just enjoy good stimulating relaxing oral sex.
From the other side, as a total bottom and a cock sucker. i find the recipients land in two general categories, though all have Their individual nuance.
For me, the hardest Guy to suck is someone who gives no feedback. i need to know He is enjoying what i am doing, that i am succeeding at giving Him what He desires/needs. If i do not perceive that, i feel it becomes mechanical. On the other hand, if i perceive His pleasure and lust, that becomes a form of control that connects too, evokes, my own lust/need.
The evoking and connecting of mutual desire/need is what makes for a mind blowing experience to me. Any kind of one sided sex shuts me down, and to me, it becomes "one sided" if the desire/need is not mutual.
i can go on and on and on. When i am with Someone Who is obviously loving what i am doing, i do not get tired. (edit: re-reading this, i think the main reason i do not "get tired" is because i am getting what i need/want, which is evidence of fulfilling His pleasure/desire/need. Orgasm is obvious evidence of that, but not the only? So my lust and longevity seem sort of dependent, or at least fed, by His need/desire). "dependent" is not a perfect word because i have my own desire to suck cock apart from Him, but they seem intertwined). When there is chemistry, i suspect my obvious expression of lust also fuels His, but even though it's sort of reciprocal, the Top is in charge... even though i am (seemingly) doing all the 'work.' His expression of desire/need is His foot on my 'gas pedal,' He is fueling and driving my lust.
When a Man does not ejaculate, i feel i have failed... that i am not done. I know a lot of bottoms/cocksuckers are focused on the Tops semen, and really seem to objectify Him in that? That's not what i want or feel, what i want is to know i have succeeded at giving Him pleasure and His semen is a result of His orgasm. i do crave His orgasm inside of me, not just His orgasm... but inside of me.
Nott that my sucking His cock has to always result in His orgasm or be about giving Him an orgasm. It depends on the perceived intent. If my perception from the start is He just wants to have His cock where it belongs (inside a guy who has need/desire for Him), i love the connection of Him knowing He can put His cock in me anytime He needs/wants. But if i perceive His need/want is for orgasm, release, i feel i have failed if i do not give that to Him.