We are all familiar with the notion that a chain is only as strong as its weakest link, it makes absolute sense.
However, not a lot of us have ever considered the idea that our weakest link could kill us, and yet, it can.
On January 28, 1986, the spaceshuttle ‘Challenger‘ exploded 73 seconds into its flight, killing the 7 aboard.
Challenger exploded due to a known fault, something that engineers had been warning about for some time, a faulty O-ring design. What is in effect a cheap rubber piece, a simple part of a hugely complex design proved to be the weakest link, and caused the catastrophic failure.
Everything else in the launch worked absolutely as per expectations and specifications.
The simple known problem, a cheap part, was the weakest link and brought it all undone.
As you remove potential sources of variation from a process, the average level of reliability and repeatability of increases, and the tension in the system increases as a result. Therefore, when one link fails, the failure becomes more painful, obvious, and sometimes hard to fix. The management task is to identify the potential problem before it becomes one, and remove it.
That is why, at the core of the Toyota Production System, you have an ‘Andon‘ system, which enables anyone to bring a halt to a production process to fix a potential problem before it becomes a failure.
The Rogers commission set up to investigate the Challenger disaster, amongst a raft of findings was highly critical of the NASA culture that prevented the well known and documented concerns with the performance of the O-rings being addressed. Of particular concern was the performance of the O-rings in the cold weather that occurred during the night before the launch. The temperatures experienced on the night of January 27 were way below specifications, and there had been no testing done to gather data on what might happen under those conditions, and serious concerns had been formally expressed.
Had there been a simple Andon system in place, rather than a Byzantine hierarchical culture, the launch would not have proceeded, and the disaster been averted.
Your production processes may not be as life defining as those in the NASA space program, but the principals remain the same.
Identify the weak points in the chain, and ensure there is explicit go/no go, or Andon points, that enable the inevitable process failures to be caught before they do any real damage. It may cost you some time in the short term, but will pay huge dividends in your ability to reliably and cost effectively deliver to your stakeholders.