RUL is a reliability concept. It estimates how much longer an asset will perform its intended function before failure. RUL depends on condition, environment, duty cycle, maintenance quality, and failure modes. It is not the same as “years left on the depreciation schedule,” and it is not the same as OEM service life minus age.

We looked at our four big-impact, highest-ranked solutions over the past four years. These have a big impact on our company because they...