Distinct Attributes Rows in Dimension Tables

There are two cases where it is a good idea to create rows in dimension tables containing distinct attributes values. The first one is prospect rows in the customer dimension. The second one is unsecuritised rows in the security dimension. Prospects (prospective clients) can either be put in the customer dimension, or in a separate table (prospect dimension). Sales fact only uses customers, so there is no problem there. But Sales Pipeline fact uses both prospects and clients, so if we separate them into different dimensions, we have a problem.