…Your watch, though it be good, through want of skill
May fail to do according to your will.
Suppose the balance, wheels, and springs be good,
And all things else, unless you understood
To manage it, as watches ought to be,
Your watch will still be at uncertainty.
Come, tell me, do you keep it from the dust,
Yea, wind it also duly up you must?
Take heed, too, that you do not strain the spring;
You must be circumspect in every thing,
Or else your watch, were it as good again,
Would not with time and tide you entertain…
from – A Boy and Watchmaker – John Bunyan