I'd like to add another item to that 2nd M D-rate...
Since most people become creatures of habit they end up picking a similar partner i.e. in choosing their new partner and revert to a facsimile or their previous one... and the cycle repeats... this time in a shorter timeframe (as Rob pointed out) because their patience threshold is lowered.
This also points back to introspection. Few people do the introspection required to identify their mistakes and where they went wrong. E.g. Some men like women who are b1tches... so they choose a b1tch to marry again. Same thing for women.
