“…see Craig et al, 2017 ) Insights for good and service providers vary; for example, foot-in-the-door techniques (asking initially for a small commitment, and escalate later) may facilitate initial adoption, but lead to a negative shock in the future. Door-in-the-face approaches, whereby the proposer starts by asking a strong commitment, may discourage adoption but, conditional on adopting, may lead to positive surprises and higher satisfaction and retention ( Staw 1981 ; Kelly and Milkman, 2013 ). Studies in medicine have also analyzed patients’ expectations gaps (see, for instance, Bismark et al, 2011 , or O'Connor et al, 2000 ).…”