1/ Empathy for people they work with, hire and sell to. 

2/ Ability to observe, what is happening in the environment they play in, how is the market responding to a launch, or how a new hire is feeling.

3/ Being good with money and knowing the basics of fund allocation, return on capital deployed and profitability, and making sure there is money in the bank always.

4/ Resourcefulness and self-reliance – being able to find out what they need.

5/ Ability to convince potential hires to work with you, and investors to invest in your business.

6/ Sales – even if they don’t sell to customers directly, they will sell to employees and partners.

7/ Ability to think clearly, because without it you can’t make plans, or communicate effectively.

8/Decision-making because the founder’s job is to make decisions day in and day out.

9/ Perseverance and persistence – those who quit can’t make it as successful founders.

What else would you add to this?