If we're talking about Taylor, it wasn't an arrest warrant. It was a search warrant.
They specifically try to do it when the suspect they've got the warrant for is in the location to unquestionably link that suspect to whatever evidence is found.
Not to mention they don't necessarily know when anyone present is going to leave, and they can't just have a full tac-team and evidence technicians sitting outside for hours as that increases the chances of being spotted, the suspected tipped off, and evidence destroyed.
With arrest warrants, they do generally prefer to get the suspect away from home as it's less dangerous and there's no evidence to worry about being destroyed like with a search warrant. They also have more time to work with since search warrants expire after both an amount of time, or when the probable cause used to get the warrant is no longer valid.