http://www.slate.com/articles/news_and_politics/politics/2015/10/jim_webb_didn_t_do_what_it_takes_to_be_president_the_former_virginia_senator.html

Running for president is hard, grueling work that almost always ends in failure. To succeed, or even come close to success, you have to commit 100 percent. You have to campaign and cajole and speak and charm and hope that voters come to your tent, and stay for the show. And even then, even if you’re good, it’s a crapshoot.