a chain is only as strong as its weakest link» An organization (especially a process or a business) is only as strong or powerful as its weakest person. A group of associates is only as strong as its laziest member.
a different ballpark» Something totally unrelated or of a vastly different scale or scope.
a drop in the bucket» An effort or action having very little overall influence, especially as compared to a huge problem.
a leopard cannot change its spots» One cannot change one's own nature.1597, William Shakespeare, Richard II Act i, Scene 1 (First Folio):King. Lyons make Leopards tame.Mowbray. Yea but not change his ?pots.1611, King James Version of the Bible, Jeremiah 13:23:Can the Ethiopian change his skin, or the leopard his spots?1820, Walter Scott, Ivanhoe Chapter 32:End now all unkindness. Let us put the Jew to ransom, since the leopard will not change his spots, and a Jew he will continue to be.1918, Johnston McCulley, Thubway Tham's Inthane Moment:The leopard cannot change his spots, old boy.
a miss is as good as a mile» A failure remains a failure, regardless of how close to success one has actually come.
a picture paints a thousand words» A visualisation is a better description than a verbal description.1971, David Gates (of Bread), If, from Manna album:If a picture paints a thousand wordsThen why can't I paint you;The words will never showThe you I've come to know.1989, Alan Kay, quoted in K?o-tung Huang, Timothy D. Huang, Introduction to Chinese, Japanese and Korean Computing, World Scientific, ISBN 9971506645, p. 9:Most human beings, no matter how familiar they are with abstract symbols, respond to voice and images better than written language. In other words, A picture paints a thousand words.2006, Paul Shakespeare, Building a Dune Buggy: The Essential Manual, ISBN 1904788734, p. 52:See accompanying diagram: a picture paints a thousand words, and all that!
a spoonful of sugar helps the medicine go down» An otherwise unpleasant situation can be pleasant when a pleasant aspect is deliberately introduced.1999, Eli Yassif, The Hebrew Folktale: History, Genre, Meaning, Indiana University Press, ISBN 0253335833, page 372,One is known as the "sweetening parable," that is to say a spoonful of sugar helps the medicine go down. Thus, when the aim is to preach to the people, to guide them along the "bitter," arduous path of upholding burdensome precepts and prohibitions, a tale can lighten the load, make the "medicine" easier "to swallow."2001, Maureen Reagan, First Father, First Daughter: A Memoir, Little, Brown, ISBN 0316736368, page 319,It put some fun into the tedious business of preparing for a presidential debate. A spoonful of sugar helps the medicine go down, right?2004, John Hoover, How to Work for an Idiot: Survive & Thrive... Without Killing Your Boss, Career Press, ISBN 1564147045, page 11,If a spoonful of sugar helps the medicine go down, a barrel of laughs can wash down the big pills you might need to swallow.
a stopped clock is right twice a day» A normally unreliable person or instrument can occasionally provide correct information, even if only by accident.