I agree that selection should be random and unbiased. However, there is a problem that will only grow with time: currently, the number of submission grows from week to week by ~50 songs. If that continues, we will have ~500 submissions by the end of this month, ~700 submissions by the end of next month, and so on. Of course, the rate of growth might slow down, but there will be some growth in any case. The probability for active viewers to have their song picked will reduce over time.
At the same time, we can take it as a given that there are and always will be people who submit a song and then stop watching the stream at some point. The main question is: is it fair to remove songs from people who are no longer watching, so that active viewers do not have their chance reduced by abandoned songs.
If the answer is yes, then we need some system to expire abandoned songs.
The current proposal is to reconfirm your submission once a month if you are an active viewer. This would maintain the same probability for all viewers who watch the stream at least once a month, including YouTube viewers. Everyone else will have a "soft expiry" that retains the song but lowers its probably.
If the answer is no, then we can go back to a system without expiry. But then we have to accept that the pool will grow over over time.
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