Nothing in Jeb Bush’s presidential candidate is as enthusiastic as the logo he released on Sunday: Displaying his first name in blood red, the logo is capped off with an over-eager exclamation mark.

That loud punctuation feels far too insistent, like a back-slapping salesman eager to assure you that you are making the best deal of your life.

A barking salesman doesn’t always believe in the product, and the aggressiveness of Bush’s logo is belied by the listlessness of his campaign. Last December the editors of The Wall Street Journal complained that “Mr. Bush has sometimes seemed diffident about running, and a half-hearted campaign won’t work against [Rand] Paul, Ted Cruz and Scott Walker, much less the Clinton tong.” Writing in The New Yorker, Alec MacGillis also used the word “diffident” to describe a campaign announcement by Bush.

Why does Jeb Bush want to be president? The use of the descriptor “diffident” is one way of saying we don’t have a clear answer to that question. Running for the White House is a gruel: It’s time consuming, often humiliating, and sometimes damaging to one’s psychological well-being or family happiness.

To work so hard for so elusive a goal, most candidates need the fuel of personal ambition combined with an ideological agenda. Bush seems to be lacking in both. Hillary Clinton hopes to break the ultimate glass ceiling, Senator Bernie Sanders to push the Democratic party to the left, Senator Rand Paul to re-orient the Republicans in a more libertarian direction, Senator Ted Cruz (among many others) to be the new Reagan.

No such overarching fusion of personal and political destiny is evident in Jeb Bush. He’s running, it seems, because his wealthy supporters think that there is a vacuum in the GOP. The party needs to put a more moderate visage and the other major candidates are too far to the right. But the role of Jeb-the-moderate sits uneasily with the candidate’s own political instincts, which are more in sync with the party’s right-wing base than commonly recognized.

George H. W. Bush won the presidency by promising a “kinder, gentler America.” His son attained the same office by a program of “compassionate conservatism.” Jeb has, historically, been far less eager to hedge ideological commitments to the right. "We have to dismantle the welfare state if we have any chance of solving our crime problem," Bush told an audience in 1994 during his first bid to be governor of Florida. He once described himself as a “a head-banging conservative” and as governor of Florida ran an administration that was more solidly to the right, complete with support for “stand your ground” gun laws and a steep tax cut for the rich, than his brothers had been in Texas.

Perhaps having to adopt a mask of moderation has contributed to Bush’s lackadaisical campaign. Personal reasons might also play a factor. His wife, Columba, doesn’t enjoy the political limelight or the ordeal of the campaign trail. As a Bush supporter told The New Yorker, “I remember having heard Columba say, ‘Jebby really loves politics,’ and kind of sigh.”

Yet Columba’s remarks only serve to highlight how perplexing Jeb Bush’s current languid campaign is. Jeb has always been purposeful and driven. In the context of the large Bush family, where men judge each other against their father and brothers, Jeb has stood out as the serious, thoughtful one, the straight shooter who followed the expected path to business and political success. His older brother George was famously the family wastrel, the Prodigal Son who wasted much of his life in dissolution and bad business decisions only to redeem himself in middle age.

The parable of the Prodigal Son is cherished by Christians as evidence of the power of forgiveness. Yet imagine being the younger brother of the Prodigal Son. You’ve spent your whole life working hard and following the rules, and then suddenly your ne'er-do-well brother picks up all the rewards. It might sour you on the family business the Prodigal Son has succeeded in.

Jeb’s famous family name is inescapable both as a blessing and a burden. His ambivalence is caught in a letter he wrote to The Miami Herald in 1998 saying, “Is favorable name recognition helpful … perhaps.” As Jeb told an Associated Press reporter in 1994, he moved to Florida to “get out from under my Dad’s shadow.”

Yet that shadow proved impossible to ever escape. It now overlaps with another shadow, that of his older brother. In 1994, campaign consultant Don Sipple told George W. Bush he seemed very confident in his race for the governorship of Texas. “Sip, my man,” Bush rejoined, “don’t underestimate what you can learn from a failed presidency.”

If George W. Bush was on the rebound from his father’s failure, Jeb has to contend with something much more difficult: two failed Bush presidencies. In running for office, he’s trading on the family name, trying to redeem the family brand, but also weighed down by the family’s history. Faced with so difficult a task, no wonder he’s a diffident candidate.

This article has been updated.