It’s one thing to do your work. It’s another thing to test it. And I learned a lesson about this in an unexpected way last night.

Last night, I, along with several hundred people, volunteered with a charitable organization that provides food to malnourished children around the world. We were split up into groups, and each group formed a little assembly line around a table in order to fill up bags of food. Each of us were responsible for either filling the bags, weighing the bags, sealing the bags, or packing the bags.

My job, along with another, was to take care of sealing the bags for our group. For the first several minutes, things were going well. I was taking my time, testing each seal to make sure it was airtight. Things were great, and after a while we began to quicken the pace as we settled into a groove.

But then it happened. One of the bags, as it was being placed in the box, began to spill out rice — we had discovered our first bad seal. It was surprising and frustrating, but we simply refilled it and resealed it, thinking it was just a one-off incident.

And then it happened again — another bad seal was discovered as it was being packed.

And then again.

Over the next few minutes, several defective seals were found. And for me, it was embarrassing, because I had the responsibility of making sure they were sealed. I was frustrated, and I’m sure others were also, as we had to refill and repack several bags during those few minutes.

And through that experience, I learned again the value of testing. Things had been going well, and so I began to not be as diligent in testing each seal. But as soon as the bad ones were discovered, that changed. After a few bad bags, I began to take a different approach. Before handing them over to be packed, I shook each bag vigorously (and upside down, too) to make sure there were no leaks. I figured it was better to catch any issues early, than to wait, and cause issues (and frustration) down the road.

It did little good to simply give the bag a cursory shake. I might find major issues that way, but could potentially miss minor ones. So I decided to make sure I tested each one thoroughly upfront. It may not have been needed, but it did increase my confidence that no bags that left my hand were defective. It took a few extra seconds, but in the end, that little bit of time was worth it. If the mistake got passed on, not only would I have to fix it again, but it would also make a mess for the packer, wasting his time too. That, and if I did find an issue, I would have immediate feedback as to what may have caused the problem.

In the end, no further bad seals were found throughout the night, which was a relief. Unfortunately, it took letting a few bad ones through for me to learn my lesson.

In life, I’m learning that it’s good to test early and test well. It does little good to only test your work in a cursory way. Sure it may pass the initial test, but that doesn’t provide much confidence that it will continue to work down the road when it really counts.

It’s like putting up a shelf, but never putting much weight on it because you’re afraid it’s going to break. But it’s better to test it up front and know if it’s going to hold, than to put it up, and hope that it doesn’t fail when you’re not expecting it.

Whatever your work, don’t be afraid to test it. And test it well. If there’s a problem, it’s better to know sooner rather than later. Often it’s cheaper and quicker to fix it now than down the road. And if you test it well, and it passes, you’ll have a far greater confidence in it than simply hoping for the best.