Paying Off Loan vs Re-Investing Cash Flow?

[Rory Cox]

What are some thoughts on saving cash flow vs paying off mortgage faster?

Spoke with an older investor today who likes paying off mortgage faster. But could be bc he's been in the game so long he has excess cash flow (got started in 1976 in SF). He also doesn’t sell, he just rents out units. 

Do you like to use extra cash flow to put towards other investments or pay down mortgage faster? 

Looking forward to learning from a variety of perspectives on this topic.

thanks as always!