The purpose of this is to give the executives an incentive to increase the value of the stock. People don't 'sell' stock options, they exercise them by buying the stock. Some may turn around and immediately sell them to pocket the profit. It's better to hold them for at least a year so that the increase becomes a capitol gain tax, not an income tax.
Executives may have an incentive to increase share value, but they have failed. Article updated with following:
>>Heavy insider selling has been ongoing at GM since I wrote about a SIGTARP report in September of 2014 that unveiled excessive pay at GM. The report found that the top nine executives at GM saw income rise from $32,307,500 to $35,335,000 in 2013.
During the 12 month period from March of 2013 to March of 2014 eight GM executives sold over $36 million worth of shares. Insider selling has not seemed to slow as executives continue to cash out while GM shares flounder.<<
Taxpayers lost billions, bondholders hosed, Mom and Pop shareholders who bought on the hype have been burnt. Cronies make their millions. As SIGTARP stated, EXCESSIVE PAY!