Should there be a comma after "proactive"?

[Kohyoongliat]

The top bosses tend to be proactive not reactive.

Should there be a comma after “proactive”?

Thanks.

[NearlyNapping]

I would use a comma, but I think a lot of people would not.

[Anglophile]

Yes. You are right.
But is it ‘The top bosses’ or ‘The top brass’?

[Masme]

You have an eye for detail!