Botswana is one of the safest countries in Africa, there is very little chance you'll have any problems with crime within the country. The greatest danger of self-driving in Botswana is animals on the road and you shouldn't drive in the dark for this reason. An additional danger is breaking down in the remote wilderness and not being able to self-recover. The road may be infrequently driven and much of Botswana does not have mobile reception so you must always have enough water and food for an extra few days.