It's easy to take for granted the things we depend on in our everyday lives. We expect everything from our refrigerators to cell phones to our preferred means of transportation to just work correctly, without disruption or fail, day in and day out, for however long we chose to use them.
But all things can suddenly fall apart, especially things that have hundreds if not thousands of parts and an equal number of screws or bolts to hold them all together.
I am not getting creative with a metaphor about life. health, or relationships here, BTW, I'm being literal - an occasional check to ensure that the important parts of the things you routinely depend upon are in good running order can prevent a mechanical failure or worse from happening.
But yeah, that does apply to life, health, and relationships too I suppose.