But gaining momentum and power requires money and leadership. Unless a grassroots movement can create those things themselves - which would be quite rare - inevitably a true grassroots movement is going to be co-opted by someone seeking to use their popularity. Thus the origins of the movement are always likely to be questioned by the opponents, because plenty of evidence of funding and leadership are going to appear. Placing them in a chronological order to determine the 'grassrootedness' of the movement is going to be tricky, unless someone kept very careful notes. Which is also very unlikely.