Not sure I agree here. Running a single company allows you to focus exclusively on that company, but providing you have the bandwidth there's no reason you can'

Not sure I agree here. Running a single company allows you to focus exclusively on that company, but providing you have the bandwidth there's no reason you can't do something else as well. I run a company as a single founder and it takes up a lot of my time, but I also run another company with a co-founder and I find that the two unrelated companies both benefit from me being involved in the other.