>Diving seems like one of the recreational activities where it is easy to end up doing something much riskier than you intended (another I'd say is alpine hiking)
You are absolutely correct, in mountaineering risk-management you have two risks an objective an subjective.
If you do hiking, the objective risk is low (hey i am just wandering), but the subjective is often much higher then one thinks (falling rocks, rapid weather change, out of water, break you angle, no way to call emergency, aggressive mother-cows etc.).
If you plan to climb a Wall the objective risk is obvious (you can fall down, rocks break out and hit you etc), and because of that you are already aware of those risks, the chance that you calculated the subjective risks in too, is much bigger.
You are absolutely correct, in mountaineering risk-management you have two risks an objective an subjective.
If you do hiking, the objective risk is low (hey i am just wandering), but the subjective is often much higher then one thinks (falling rocks, rapid weather change, out of water, break you angle, no way to call emergency, aggressive mother-cows etc.).
If you plan to climb a Wall the objective risk is obvious (you can fall down, rocks break out and hit you etc), and because of that you are already aware of those risks, the chance that you calculated the subjective risks in too, is much bigger.