pbl22- You're correct re: the meaning of my question. I was writing a response to Craig saying the same thing. Thank you for clarifying.

Unfortunate if it is indeed the fact that they get lost. It's fine if the flight that gets you over the line is an 8SP domestic add-on and you only needed 5SP, but what if it's a 480SP long-haul BP fare? Losing 475SP is not exactly a write-off.