Optimize your inner MacGuyver

This is so profound- yet so simple. If you can get a handle on this it will revolutionize your abilities in just about every aspect regarding mechanics.
The role of a machine is to transmit motion, energy, force in a predetermined manner to accomplish a goal.
Machines that have moving parts eventually wear out and cease to perform the function that was intended. Why?
In order for the assemblage of parts in a machine to fit and work together, they are made to specific tolerances- not too little or it's too tight; too much and it's too loose.
When something wears out it's because friction, motion, stress has removed material from the part causing it to not fit and work together with the other parts because the tolerance has been exceeded. The logical solution? Replace the material that was lost restoring proper tolerance, or fill in the gap with a suitable material- what I call "shimming"
It's what you're doing when you put oversize bearings or pistons in an engine. When the front suspension becomes worn and loose sometimes "shims" can be used to remedy it. When a tire wears unevenly wheel weights are used to balance out the missing rubber from the tire. Sometimes a bolt or screw comes loose, distorting or wearing out it's original location and a larger one is used to fill in the slack. You've heard of unscrupulous mechanics adding sawdust to a worn transmission or differential- it's all the same concept.
In situations where something has worn out, and a replacement part was unavailable or not feasible, many times have I done some creative, (although unorthodox) and inventive shimming to save the day. An example: A well oiled sliver of thin copper tape on worn electric motor bearings keeps the shaft from wobbling and shorting out.