Instant repentance?

peace,
I didn't quite understand what Maimonides said –
How excellent was the virtue of repentance yesterday, this was separated from the Lord God of Israel, as it is said, "Your sins have separated between you and your God, crying out and not being answered, as it is said, "Because you have multiplied prayer, etc., and he has made commandments and has destroyed them before him, as it is said, "Who has asked this of you? Who has trampled your gates? Who has also shut the doors among you, etc.?" And today he is glued to the Shekhina, as it is said, "And you who cling to the Lord your God , crying out and being answered immediately ," as it is said, "And before they call, I will answer, and you will do commandments and receive them with peace and joy," as it is said, "For God has already pleased your works, and no more than that you desire them," as it is said, "And a pledge to the Lord is the offering of Judah and Jerusalem, as in the days of old and as in former years."
 
It seems simple and easy and in less than 24 hours.
I know from personal experience and from many others that this is not exactly the case.