Randomness is a means to effect changes without wasting effort on planning them, exploiting the power of chance to solve problems and open new vistas. After all, human kind is a case in point for 'randomness in action" as Charles Darwin taught us.
In a dynamics of repeated trying of the very same effort (and repeated failing) it is highly recommended to make random changes regardless of any rationale to support them. In any action there are numerous factors that may be randomly changed, and should be. If the reason for the repeat failure is an attribute of the action, which is totally unsuspected, then the active randomization would flush it out.
Randomization is effective for human efforts as well as for AI plans. In fact some of the most stunning achievements of artificial intelligence took place by practicing this TryAgain randomization in a very persistent way.