Investors want quick profit. Development takes a time, it is necessary to wait till the price of the tokens will grow.
It is possible to earn big profit only on speculations and market manipulations. The time of mass speculations has finished in 2017.
Even now there are a lot of speculation on cryptocurrency market. Very often tokens are used for speculations and do not have any practical use.
It is hard to speculate with Bitcoin because of the big capitalization of Bitcoin, but it easy to speculate with tokens with small capitalization.