1. Have many orgasm during one single sexual intercourse
Orgasm and ejaculation are two different things, often confused because these two things happen "almost" simultaneously. In reality, there are a few fractions of a second between the moments of orgasm and ejaculation. Injaculation makes it possible to distinguish these two phases and physically separate them. It is possible to have the pleasure of orgasm without ejaculating, and that way have multiple orgasms during a single sexual intercourse.
2. Delay more and more ejaculation !
A successful injaculation is not accompanied by the resolution phase : after a injaculation you keep a strong erection, but your level of excitement goes down. Therefore, you can continue until your partner is fully satisfied. In addition, you will notice that after a injaculation your excitement will stay completely stable. This means that you can have strong stimulations without any risk of ejaculation.
3. Have stonger orgasm
You will also realise that the more you delay your ejaculation (having intermediate orgasms), the more the final orgasm will be strong. That allowes you to synchonize your final orgasm with your partner, with perfect timing.