Solo: A Star Wars Story has racked up a bit of a reputation for being the problem child among Lucasfilm's current in-development projects. The first signs of trouble arose when Kathleen Kennedy flexed her executive muscles and fired directors Chris Miller and Phil Lord well into Solo's development. This massive production shakeup struck fear into fans, causing some to wonder if Kennedy was playing it too safe by firing directors over their artistic vision. Worse yet, Alden Ehrenreich, the actor portraying Han Solo, was saddled with an acting coach on-set in order to ensure his performance was up to snuff. Couple these problems with the fact that the movie's arriving in four months and Lucasfilm still hasn't publicly released a single second of footage, and it's easy to see why people are getting worried (studio execs included, we bet).
As a result of these problematic developments, Solo's got quite a bit to prove. First, it's got to show it can overcome a troubled production history. Then, it's got to justify its place in the Star Wars lineage, since any story with Solo as a hero could potentially, and retroactively, invalidate his character's starting point as a scoundrel in A New Hope. Lastly, it's got to do both of these things so well that fans don't catch Star Wars fatigue, especially considering The Last Jedi was only just a few months prior and new Star Wars installments are now expected every year.
In short, Solo's got everything to prove and everything to lose, which is probably why he doesn't like to be told the odds.