Explicit extrinsic rewards and punishments have sometimes been found to have a counterintuitively inverse effect on behaviors when compared to intrinsic rewards.
ɛksplˈɪsɪt ɛkstɹˈɪnsɪk ɹᵻwˈɔːɹdz ænd pˈʌnɪʃmənts hæv sˈʌmtaɪmz bˌɪn fˈaʊnd tə hæv ɐ kˌaʊntɚɹɪntˈuːᵻtˌɪvli ɪnvˈɜːs ɪfˈɛkt ˌɔn bᵻhˈeɪvjɚz wɛn kəmpˈɛɹd tʊ ɪntɹˈɪnsɪk ɹᵻwˈɔːɹdz.