Unplanned Downtime: Why It Happens and How To Prevent It

Oct 20, 2020 | Manufacturing

Unplanned downtime is the worst. Literally. Here are stats and estimates from around the internet:

  • Factories lose at least 5% and up to 20% of productivity due to downtime (widely cited estimate).
  • A single hour of downtime costs most organizations $100,000 to $300,000 (source).
  • 72% of organizations say that zero unplanned downtime is one of their top priorities (source).

Before you can solve a problem, you need to understand it. Let’s look at some top causes of unplanned downtime and ways to prevent it.

Human error

Manufacturing has a people problem, and we’re not just referring to the industry’s difficulty finding qualified workers. Human error is responsible for 23% of unplanned downtime, which is a larger proportion than is found in any other sector.


  • Training and resources. People don’t want to make mistakes — for the most part, errors come from a lack of information. To prevent this, make sure you’re providing your employees with the training and resources they need to do their jobs well. This includes everything from clear SOPs to initial and refresher training on all equipment.
  • Automation. Another way to reduce human error is to eliminate the possibility of it happening through automation. This doesn’t have to be an all-or-nothing initiative. If you can identify one part of your process where errors frequently happen, then automating just that part can go a long way to reducing your downtime as a whole.

Equipment failures

At least 70% of companies don’t know when their equipment is due for maintenance, upgrade, or replacement. This explains why equipment failures are a significant source of downtime.


  • Predictive maintenance. According to a GE study, moving from a reactive maintenance model to a predictive maintenance one can reduce unplanned downtime from an average of 8.43% to 5.42%. With 60 minutes of downtime equal to hundreds of thousands of dollars in losses, those three percentage points can make a substantial difference.
  • Buffering. Typically, just one machine on a line fails at a time. But, when it stops processing, all of the other machines have to stop as well. By adding buffers to your line, you can protect the rest of the line from the malfunctions of a single machine. Read more about buffers.

Nonoptimal material flow

Sometimes machines are down because there’s a problem. And, sometimes, they just don’t have anything to do. If your equipment is capable of running, then it should be. Period.


  • Material flow analysis. If your machines are sitting idle, you may have a material flow problem. Specifically, your cycle time contains too much wait time. If you Google “material flow analysis template,” you’ll find a variety of free resources to help you analyze, and identify issues with, your material flow.
  • Accumulation. Often, machines don’t have anything to do because they’re waiting for products from a slower machine upstream. That slower machine is a bottleneck in the entire process, and bottlenecks can be very costly! Accumulation systems can help you compensate for bottlenecks by ensuring that they don’t limit your overall run rate more than is absolutely necessary. Calculate your line efficiency to see where accumulation can help.

If zero downtime is your goal, we can help. Contact us to learn more about our automation, buffering, and accumulation solutions.