"If you do what I do you are going to end up making people sometimes happy and sometimes unhappy, " he says.

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Sometimes she is unhappy, and then she will tell us, I am dying.

NEWYORKER: Magda Mandela

Denton sometimes encounters people who are unhappy with what he is doing.

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Junior doctors are also deeply unhappy with the long hours - sometimes well over 60 a week - claiming it affects their performance, putting patient care at risk.

BBC: Junior doctors still heading for strike

"Sometimes, when players don't play they think the coach is unhappy with them but he always made me believe in myself and to try harder, even if I didn't play, " explained Bellion.

BBC: How Bellion bounced back

When we were talking about a few unhappy customers as a small percentage of the market, it was sometimes easy to dismiss a few disgruntled voices.

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