In a previous relationship, she liked, or was okay with changing positions, so after a few minutes in one position, we'd stop for a few seconds to get into another position. For me, missionary is always the position that I cum quickest in, so I'd like to end with that position. Since she really like doggy style and also riding me, we usually started with those, then ended up in missionary where I would cum. I think those sessions of usually lasted about 10 minutes plus of penis in vagina action, which is actually quite a long time.
With my wife, she likes to finish in whatever position we start out in, so lasting 10 minutes plus rarely ever happens, and if we start out in missionary, I'm very lucky to make it to 5 minutes.
There is some good advice above. Vary your pace and changing positions has always worked for me.