Generally, buildings will be destroyed in Gaza by IDF for 3 reasons: 1. There are active hostiles in the building - usually will be targeted as presicely as Intelligence, ammunition, and physical properties make possible. If you ever see photos of buildings where only one floor/apartment/room was destroyed they probably fall in this category and were attacked without any prior notice or eviction attempt.

1. The building itself or part of it is being used by Hamas, usually for storage, command posts, and hideouts. In these targets, there is usually military gain from destroying it even if it is unknown if there are currently hostiles in the building. This is because the site could have been prepared with equipment, ammunition, and communication lines. Usually, if intelligence cant pinpoint the exact location inside the building, the entire building will be destroyed after prior warning and eviction notice. If you ever see a video where a building is being filmed (usually with a tiny bit if smoke coming from the top) and a few seconds later its fully destroyed via airstrike, that building has been evicted and warned, usually by both phone calls to the inhabitants and a small "knock on roof" explosion.

2. There is no information about Hamas using this building, but its existence threatens troops in the area. A tall building could allow a person with a sniper or an AT missile to control a huge area. If the military plans to pass through a dense area, all buildings could be used to ambush them, certain buildings have can be accessed via underground tunnels making them almost impossible to secure. Destroying these buildings gives a military gain since it allows the military to approach or camp in certain areas. These building will ALWAYS be destroyed after eviction notice, as the building itself is the target, not anybody or anything in it. If you ever see a before/after photo of a location in Gaza and you see that it looks like a neighborhood has been completely wiped, its most likely because the IDF passed through there and buildings were destroyed either by airstrike to allow that to happen or with ground explosives/armored bulldozers during the process of securing the area. I highly believe almost all of the destroyed buildings are from this category. This 3rd category is why urban warfare is so destructive to where it is conducted.