"An excessive use of exclamation marks is a certain indication of an unpracticed writer or of one who wants to add a spurious dash of sensation to something unsensational". -H.W. Fowler
Or, as Lynne Truss puts it, "In the family of punctuation, where the full stop is daddy and the comma is mummy, and the semicolon quietly practices the piano with crossed hands, the exclamation mark is the big attention-deficit brother who gets over-excited and breaks things and laughs too loudly". Months after starting it, I have finished her book Eats, Shoots and Leaves, and whole-heartedly recommend you read it (especially if you're a grammar stickler; otherwise, much of her humor will probably be lost). As the infamous modernist George Bernard Shaw laments, " The man that cannot see that [the correct example]. . .is the best looking as well as the sufficient and sensible form, should print or write nothing but advertisements for lost dogs or ironmongers catalogues: literature is not for him to meddle with".
"I never have found the perfect quote. At best I have been able to find a string of quotations which merely circle the ineffable idea I seek to express".
"I improve in misquotation".
-Cary Grant (1904 - 1986)
"People will accept your ideas much more readily if you tell them Benjamin Franklin said it first".
-David H. Comin
"A facility for quotation covers the absence of original thought".
-Dorothy L. Sayers (1893 - 1957), Lord Peter Wimsey in "Gaudy Night"
"I might repeat to myself slowly and soothingly, a list of quotations beautiful from minds profound––if I can remember any of the damn things".
-Dorothy Parker (1893 - 1967)