[ajb]

Because you don't know what the lighting is, what the sensor is, and what kind of shit the camera app and ISP are doing to the image without telling you

I recently tried to show some images to a vet. Something in my phone fucked up the amount of red in the image, making them useless (guess what, figuring out how much blood is present is pretty important for medical applications)

Probably at some point we will all have a separate medical camera with specified response and with a specified led illuminator. Apple will probably get their phone certified in some medical camera mode. Right now I don't think phone cameras can be trusted

Not all applications need accurate colour, (no idea about cancer checks) but some really do.