A vision for success and shareholders willing to see it through can give a business a competitive edge. : As boards and shareholders rate CEO performance this proxy season, they should weigh evidence of the value of long-term thinking: Companies boasting the longest tenured CEOs also tend to attract the best shareholders — those with the longest holding periods and highest concentration levels. That’s yet another advantage to companies and managers who attract such “quality shareholders” (or QSs), up there with curbing activism, countering proxy advisor power, and offsetting short-term pressure.