The examples in the bible refute the common attempts to limit "when" the Holy Ghost is given.
Do you think it comes immediately upon belief? There are biblical examples where that isn't the case.
Do you think it comes immediately upon baptism? There are biblical examples where that isn't the case.
Do you think it comes immediately upon [insert your favorite doctrine here]? Let's pass that doctrine through the examples given in the bible and see if it stands.
My personal thoughts as to WHY people try to make the "when" limitation is usually one of 2 reasons
1. Ignorance: (which only means they don't know. It's not an insult)
1a) Maybe they don't actually know what the Holy Ghost is, or what it's like when He arrives
1b) Maybe they don't know that the biblical examples show something other than what their church teaches. (that's dangerous if they find it and say so)
2. Pride:
2a) Maybe they're afraid to admit they don't actually know something that they've been told "every believer" should know.
2b) Maybe they're afraid to consider the possibility that not only they themselves might not know, but that perpaps their whole church has been the blind being led by the blind...or something similarly scary. It's just easier to believe otherwise.
2c) Maybe they personally are a proud person and think they can just ignore or discredit the examples given in the bible (as though God made a mistake or didn't know how to give examples that "fit today")
2d) Maybe they're a pastor, elder, spokesperson or official in a church and have been taught it would be "blasphemous" to choose to unashamedly cast off any church doctrine that doesn't match the scriptural examples.
Or maybe they just haven't considered that the bible doesn't specify a "WHEN".
Jesus didn't tell his disciples "WHEN" they would be baptized with the Holy Ghost...only to tarry until they get it. Perhaps we are to do the same. But that would also mean we'd have to acknowledge our ignorance like they were able to do in Acts 19:2 <--(I love those people) and make ourselves vulnerable to attack (especially from our church buddies who would cry "Doubter! Blasphemer! Destroyer!"
BTW... There's a reason why Nicodemus came to Jesus by night.
Love in Jesus,
Kelby