Well keep in mind that the inputs to the algorithm can vary. Randomization can help avoid a bad input from throwing your algorithm off. A simple example of how

Well keep in mind that the inputs to the algorithm can vary. Randomization can help avoid a bad input from throwing your algorithm off. A simple example of how randomization helps is quicksort: if we pick the pivot to always be the first element, then any sorted array will cause worst-case running time. But by randomizing the pivot, we can do well (in expectation) for any input.