What does it mean to 'devalue democratic process'? I think there is a problem with repeating elections and referenda, which is the following: Often, only a certain agent(in our case, the parliament) has the power to repeat/initiate referenda. If they are allowed to repeat referenda, then they get more potentially unjustified power in determining policy outcomes according to their preferences, since they can repeat the process until they get a result they want.
But on the other hand, it seems odd to claim that a referendum binds until eternity, or at least that it's not sensitive at all to changing circumstances.
And initiating a referendum through popular means(maybe increasing the required number of signatures for each repeat of the referendum) removes this problem of giving some agent unfair power over policies. But you think there is a problem just about repeating itself, and I don't understand what that is.