No MTBF Blog

A site devoted to the eradication of MTBF. The following excepts are recent posts of the

NoMTBF blog. Click through or visit nomtbf.com to learn more about the perils and what you can do instead of using MTBF.

Fill out my online form.
HTML Forms powered by Wufoo.

You email is safe here – we will not share with anyone else.

  • Consider the Decision Making First
    Consider the Decision Making First Reliability activities serve one purpose, to support better decision making. That is all it does. Reliability work may reveal design weaknesses, which we can decide …
  • What is Wrong With Success Testing?
    What is Wrong With Success Testing? Three prototypes survive the gauntlet of stresses and none fail. That is great news, or is it? No failure testing is what I call success testing. We often want to c …
  • Defining a Product Life Time
    An Elusive Product Life Time Definition The following note and question appear in my email the other day. I had given the definition of reliability quite a bit of thought, yet have not really thought …
  • MTBF is Not a Duration
    MTBF is Not a Duration Despite standing for the time between failures, MTBF does not represent a duration. Despite having units of hours (months, cycles, etc.) is it not a duration related metric. Thi …
  • The Fear of Reliability
    The Fear of Reliability MTBF is a symptom of a bigger problem. It is possibly a lack of interest in reliability. Which I doubt is the case. Or it is a bit of fear of reliability. Many shy away from th …
  • Being In The Flat Part of the Curve
    What Does Being In The Flat Part of the Curve Mean? To mean it means very little, as it rarely occurs. Products fail for a wide range of reasons and each failure follows it’s own path to failure. As y …
  • A Series of Unfortunate MTBF Assumptions
    A Series of Unfortunate MTBF Assumptions The calculation of MTBF results in a larger number if we make a series of MTBF assumptions. We just need more time in the operating hours and fewer failures in …
  • Time to Update the Reliability Metric Book
    It is Time to Update the Reliability Metric Book with Your Help Let’s think of this as a crowdsourced project. The first version of this book is a compilation of NoMTBF.com articles. It lays out why w …
  • We Need to Try Harder to Avoid MTBF
    We Need to Try Harder to Avoid MTBF Just back from the Reliability and Maintainability Symposium and not happy. While there are signs, a proudly worn button, regular mentions of progress and support, …
  • 3 Ways to Expose MTBF Problems
    3 Ways to Expose MTBF Problems MTBF use and thinking is still rampant. It affects how our peers and colleagues approach solving problems. There is a full range of problems that come from using MTBF, y …
  • The Army Memo to Stop Using Mil HDBK 217
    The Army Memo to Stop Using Mil HDBK 217 Over 20 years ago the Assistant Secretary of the Army directed the Army to not use MIL HBK 217 in a request for proposals, even for guidance. Exceptions, by wa …
  • Why do we use Weibull++ over JMP?
    Why do we use ReliaSoft instead of JMP to Identify the Time to Failure? This is a question someone posted to Quora and the system prompted me to answer it, which I did. This question is part of the ge …
  • Futility of Using MTBF to Design an ALT
    Futility of Using MTBF to Design an ALT Let’s say we want to characterize the reliability performance of a vendor’s device. We’re considering including the device within our system, if and only if, it …
  • Two Ways to Think and Talk about Reliability
    Two Ways to Think and Talk about Reliability Neither includes using MTBF, btw. And, I’m not thinking about the common language definition either. Plus, I may have this all wrong. Here is the way I thi …
  • The Damage Done by Drenick’s Theorem
    The Damage Done by Drenick’s Theorem Have you ever wondered by we use the assumption of a constant failure rate? Or considered why we assume our system is ‘in the flat part of the curve [bathtub curve …
If you’d like to learn more about MTBF and how to improve your reliability metrics, let’s talk.