i thought that with burglary, the key moment is the burglar's entrance into a building. If at that moment the burglar intends to commit a crime inside the building, it's burglary, therefore wouldn't it be true that if a culprit first decides to commit a crime only after entering a building it doesn't constitute burglary? are you on the same page as me?
I don’t know what page you're on so I couldn’t tell you if we are on the same page. A person doesn’t have to have the intent to commit a crime while at the threshold of the building. He can have the intent several hours before or even once s/he gets in the building (though it would depend on the purpose of entering the building). Intent is usually extrapolated from the collateral circumstances and that is what any prosecutor would argue.