Choosing the appropriate failure management strategy or tactic to use for each possible failure mode depends upon on a mixture of reasons and considerations such as technical feasibility, experience, judgment, and whether the task is worth doing. Making the correct maintenance task selection begins with an understanding of the failure behavior or the failure mode
that is to be addressed by the maintenance practice, which means obtaining an understanding of the failure distribution model – probability density function (PdF) – that governs the failure mode.