The best things may be abused.
Nothing so good but it might have been better.
The best-laid schemes of mice and men gang aft agley. (often go awry, Robt. Burn's poem, "To a Mouse" 1786.)
There are spots even in the sun.
The best cloth may have a moth in it.
The best cart may overthrow.
No garden without its weeds.
No land without stones, or meat without bones.
No rose without a thorn. (A commonplace of Elizabethan & 17th -cent. verse.)
Every light has its shadow.
No day so clear but has dark clouds.
There was never a good town but had a mire at one end of it.
Every path has a puddle.
It is a good tree that has neither knap nor gaw. (knob, or blemish.)
It is a good horse that never stumbles. (Sometimes with the rhyming line "And a good wife that never grumbles."
~ The Penguin Dictionary of Proverbs
