Yes, maybe rare was the wrong word, sorry my mistake
I guess what I meant to say is that among the standard phals and hybrids the vast majority (including all those mass market hybrids) don't have a rest period or loose more than one or two old leaves at a time and so that is what most people are used to with Phals. Generally we are used to Phals with no leaves being at deaths door.
However there are several species (and their close hybrids) which need a winter rest and can loose their leaves as part of their natural cycle.
This is a particularly pretty example of one.