I once hold a coin and suddenly the coin that is almost $1 dump to less than $0.01 to me I move on but to some people which are newbies this can discourage them from participating in crytocurrency and make them conclude it is fraud and that brought me to a question how do you think pump and dump group are damaging crypto-currency and it's reputation??
Yes, the pimping and dumping group did a lot of damaged to cryptocurrency and they doing it through the regulators, government and FUD site or blog poster. Meanwhile, it hard to know those really behind it.