What does it mean that quantum computers are probabilistic

A probabilistic computer can store and use information in the form of zeros and ones at room temperature, while quantum machines typically operate at near absolute zero. A fundamental difference between classical computers and quantum computers is that programs in quantum computers are intrinsically probabilistic, whereas classical computers are usually deterministic. In quantum algorithms each possible result has an associated probability amplitude.

where is the graph? post the graph then ill come back and

is this supposed to be a question ?