The probability of success or failure in any single event is not always 50-50%. It depends on the specific event and the conditions under which it is taking place.
For example, the probability of flipping a coin and getting heads is 50%. This is because there are two possible outcomes (heads or tails) and each outcome is equally likely.
However, the probability of winning a game of chess is not 50%. This is because there are many factors that can affect the outcome of a game of chess, such as the skill level of the players, the opening moves, and the luck of the draw.
In general, the probability of success or failure in any single event will be somewhere between 0% and 100%. The closer the probability is to 50%, the more likely it is that the outcome will be random. The closer the probability is to 0% or 100%, the more likely it is that the outcome will be determined by factors other than chance.
It is important to remember that probability is a measure of likelihood, not certainty. Just because the probability of an event is high does not mean that it will definitely happen. And just because the probability of an event is low does not mean that it will never happen.