Model element: Change
In order to improve a type of thing, we must make some change to it.
In other words, we must introduce some variation.
This will generally consist of some change to the type design of the thing.
Note that a change can be accidental and made at random (as is the case with biological evolution), or it can be made based on some analysis, with some forethought and anticipation of the consequences (as is generally the case with human design).