The expensive silence after the sale
A family books a flat, and for the next two years the only messages they receive are payment demands. Possession day is chaotic, the anniversary passes unmarked, and three years later they buy their investment property from a competitor who simply called. Meanwhile the marketing team spends heavily on portals to reach strangers, while hundreds of satisfied owners, each knowing several active buyers, sit unasked in a forgotten spreadsheet.
Real estate treats retention as irrelevant because purchases are rare. The arithmetic says otherwise: a referred buyer costs a fraction of a portal lead and converts at multiples of it, and the referrer is someone you already served.