I really do think that the thing that holds back most prospective investors to invest on Steem is it's faucet sign-ups (mass-adoption).
For a Freemium business model like Steem, a large 'genuine' interacting user base is needed. The worth of the network is based on how many users are using it and in order for Freemium models to work, your service must be able to reach millions of genuine users.
Unfortunately for 2 years (and counting), Steem is greatly failing at this. Sign-ups via Steemit.com takes days/weeks to get approved and with them laying off 70% of their manpower, who knows now how long it would take for their team to check the queries.
The cool thing though is that Steem is now trying to provide a solution to this issue with their RC system and discounted account creation token. It's obviously still not enough but it is a good start.
Point is: the more active users are using Steem, the more likely investors are to invest backed by Metcalfe's Law. :)
They need to see an active community they can invest on. Community is the strength of this blockchain but it's also the weakness of the blockchain itself. There are several divides just as how diverse the intentions of people coming into the platform. Some communities are built to make a quick buck, some want to add value to the blockchain, and some deviants out there are experimenting. There is no clear voice about where the blockchain is heading. I think investors want direction to where their money is going to be and hopefully that direction spells ROI.
The goal of every investor is to make profit. Steemit is one lovely blockchain but I will say it lack some good merits which could be one of reasons why investor may not be encourage to invest. The Steemit blockchain is not a perfect one and I will do say I don't think there is a perfect blockchain that exist but it can thus strife to be better. Steemit isn't such a fair system, because here some people who are well connected get favoured easily unlike others
Secondly the problem of signing up, at times it takes 2weeks or more for a account to get approved. A friend of mine once signed up on a steemit a month ago and is yet to get any approval
Steemit needs to get better to encourage investors to invest
I think any prospective investor looks out for one major thing - viability. They will need to be convinced that the potential for growth and a higher returns in the future is a lot more important than the money they are parting with should they choose to invest.
Potential cannot be easily measured despite all advices and requires a keen eye as well as sticking to gut instincts. Therefore the potential investor must be positive about steems future and a subsequent rise in value in the future.