In the US we currently have the situation that many politicians' only career has been politics.

Examples:

a) Joe Biden was a politician for ~50 years. I would submit that he was trapped in a "political box" outside of which he was lost; and

b) Most Republicans in Congress are afraid that if they do not support President Trump, they will lose their Congressional seats. If that happens, they have no Plan B.

If, on the other hand, they had a separate capability - one they could use in case they lost an election - they would not be so afraid of losing a race.

Also, if they had a separate capability or experience, they would better understand the impact that legislative actions might have in a practical world outside of politics.

Ideally, if this separate capability made them literate in a subject such as Big Data Analysis, this would permits laws to be tailored to an individual citizen's set of circumstances, rather than force-fitting the citizen to conform to only one or two criteria.