Some roleplays keep going for years and years on end. Some reach a nice finishing point and stop. Some go for a few weeks or few months and then folks gradually lose interest. Some die relatively quickly, either out of lack of interest, disputes between roleplayers, or individual players running into real-life distractions.

No matter how much you loved a roleplay that either died or never even really made it off the ground, either you or someone else will come up with another idea that you love even more down the road. Best to just move on and continue seeking out new roleplays, rather than clinging to dead ones.