It is generally considered normal for ejaculation to occur in healthy men after the penis has been in the vagina for more than a minute, i.e., 2-6 minutes.

The kind of novels that go on for hours are ejaculation disorders unless foreplay is added. It's not the longer the better, as too long can be uncomfortable for women, such as pain from dryness.?

The general expectation of 30 minutes of sex is not 30 minutes of penetration, but includes 70-80% of foreplay time, and 1-3% of penetration time. That is to say, when men give women enough foreplay time, for example, men's physical strength and energy in 10%, men can give women 7-8% of the energy used in foreplay, so that women to achieve sexual arousal and close to the state of orgasm, then men and then the remaining 1-3% of the strength that is 2-6 minutes for penetration and completion of the ejaculation, rather than all the physical strength and energy in the insertion of the action.