Most notably, this method is incompatible with many large companies’ policy of merely confirming a past employee’s service, and not speaking at all to their quality. This is done to avoid claims that past a employer has sabotaged a worker’s attempts at landing a new job. So rather than say anything potentially harmful (or failing to say something sufficiently favorable), they say nothing.

Inasmuch as a return call or lack of one is either way presumed to offer insights a previous company might be unwilling to provide, this referral-check technique can’t be deemed reliable — to say nothing of other factors (laziness, business, forgetfulness, etc.) that could prevent a person from calling back.