Nope they don't expire as of now. Why would someone just keep hoarding smerits?
I can't think of any proper reason of why people will not spent their smerits. One reason can be jealously as they do not want other members to grow up quickly than themselves and hence do not send any smerit.
The system has been added to encourage quality discussions. May I remind about the fact that before this the forum was flooded with "sir I believe in bitcoin, it's a great project sir and it will go the moon sir". A lot of members were complaining about it in Meta.
jealously? It's the kindergarten here? The Bitcoin Discussion board is a good example to take, it's maybe one of the board with the lowest amount of Smerits received. Why? I'm going to tell you, it's hard to have a decent discussion, people repeat the same thing over and over they just rephrase the post above.
I read some topics with 6-7 pages, on the 7th I don't even remember what the original post was about lol. I'm not at all inclined to reward anything in such a conversation.
It's harder for shitposters in Development & Technical Discussion or Bitcoin Technical Support because either you know what you're talking about or you just shut up. Yet I see a decent amount of Smerits received in.
Ranking up quicker than others, what is that? A contest to know who has the biggest dick? We all know it's me