Becca,
This is a fantastic topic for our time. There is a leadership gap as much as there is a labor gap. People are being promoted into leadership roles before they are ready solely because there is a void that needs to be filled.
Knowing this, we have the opportunity to identify people with the traits or charactoristics that will help them make the transition smoother. We all know that just because someone is really good at their job, it doesn't make them qualified to lead others in doing the same job, totally different skill set.
My list of three traits has everything to do with becoming a "servent leader". A servent leader listens well to problems brought to them by their team. Listening means engaging in a dialogue where problems are well defined so the leader can provide action that removes the barriers to solve the problem. This brings up the second trait - Action oriented. Leaders can create a loyal following just by acting quickly, even if the problem is small. A series of small quick wins is crucial to show the team that this leader is worth following. This clears the path for larger problems to surface so the real work can be done. The last trait is self control. The tried and true attributes of being firm, fair, and consistent is still the most important trait. Nobody likes to see themselves on the outside of a system built on favoritism. Firm, fair and consistent is the best defense against creating a toxic environment in a team.
Our role is to identify those who demonstrate these traits and provide the technical as well as soft skill training they need to be successful.

Responsibility, knowledge, desire for good.