In fact your camera will catch a lot of false alarms that's why you will be spammed if you send an email on every motion detection: brightness changes, birds, wind blowing through the trees...
To reduce false positives you should use more accurates settings for each camera (with areas, buffers, warmup frames...). However kmotion has only most commons motion detection settings.
If your camera is an indoor camera maybe kmotion should do what you want. But for an outdoor usage, I advise you to use another software, which one can even live stream your cams on your smartphone ;-)