Through improving bitcoin, many investors might come back.

First that need to improved is it needs to becomes less volatile. Too much volatility kills demand; anecdotally, it remains the biggest barrier to adoption (aside from a lack of understanding) that I’ve seen locally. It might be confuse us that we really don't have proper or a stable price of btc that is why many people tend to quit this kind of work, cause its not easy to manipulate once we don't have what's so called stable price.
Second it should need to have more exchange platforms.it needs to quickly develop more trusted networks and it should need to be more liquidity as well.