Andrew Hill at FT:
A thank-you is not:
● A way of improving skills. Thanking an incompetent staff member for work only just up to standard may persuade him to work harder, but not better. That’s what training is for.
● An alternative to money or promotion. Cash is certainly a poor substitute for gratitude, but the reverse is also true. Profuse thanks may work once in lieu of a bonus. By the third or fourth year, the motivational effect of the thank-you letter tends to wear off.
● An apology. “Thank you for offering to cover for Joan after I forgot she had asked for time off”: wrong. “I’m sorry for leaving you in the lurch on Joan’s day off – but thanks for covering”: right.
● An order, as in the hollow pre-gratitude of memos that begin: “Thanks in advance for coming in over the holiday period to complete the project.”
As other studies have shown, people tend to give far more weight to negative communications than to positive ones. That suggests employers need to dispense proportionately more gratitude to offset the harsher news they often have to transmit.