Methods, systems and computing devices are provided for using a completed corrective action as evidence of a fault. The methods, systems and computing devices receive equipment status evidence and determine an equipment fault based on the equipment status evidence. The methods, systems and computing devices also create and rank a list of potential failure modes based at least in part on the determined equipment fault, recommend a corrective action to correct the equipment fault based at least in part on the ranking of the potential failure modes and receiving additional equipment status evidence indicating that the recommended corrective action failed to correct the equipment fault. The methods, systems and computing devices then associate a detection probability and a false negative rate with the failed corrective action to create additional status evidence, and re-rank the list of potential failure modes for subsequent performance based on the additional status evidence.