I feel that 95% of the action at my house is at the front door. It is for that reason i feel that one camera is not enough. It is hard to beat a good dedicated doorbell camera (ring alert, audio, viewing angle and FOV). I am on my third
. They still need some improving, mainly in false positive and lost detections and AI features.
To supplement the doorbell camera, i have two approach cameras, one for the driveway and one for the edge of the porch and front of the cars. I am going to replace my door mounted (upper left corner) HIkvision with a new Dahua that faces AT the door from 10 ft away up under the overhang, not away from the door, so i can get every angle the UPS, FedEx, Amazon people hide packages in and around my door area and see another angle and behind the door visitors. I will probably use the new 5442 turret model in a 3.6mm. If you do mount one at the door, you will want the 2.4mm for the wide field of view, but even that will likely not be wide enough at <4 ft. Modern doorbell cameras are sporting like 140 deg FOV, and still miss the package sitting against the door itself.
There are a lot of different front door configurations so YMMV. For me, i have 4 cameras covering anyone approaching the front of my house.