Self-driving cars may have a long road ahead before winning over mainstream American consumers.

According to a Harris Poll survey, charted for us by BI Intelligence, 33% of all US adults indicated they will never consider buying or leasing a self-driving vehicle. The distaste for self-driving cars was even higher among older groups, with 36% of both Generation X (ages 38-49) and Baby Boomers (ages 50-68), and 50% of Matures (69+) indicating they would never buy/lease a self-driving vehicle.

We're still years away from a time when self-driving cars are available to the general public. The fact that two-thirds of Americans are not completely averse to the technology is promising.

Still, there are clearly concerns about the safety and reliability of self-driving vehicles — 22% of respondents said they would consider buying a self-driving car when the “bugs” have been worked out. All age groups except the Millennials cited concerns about technical bugs as the main reason for not buying a self-driving car.

Google will have to allay those concerns if it wants its autonomous cars to catch on with the public. On Monday, Chris Urmson, the director of Google's self-driving car program, announced that the company's prototype vehicles have been involved in only 11 minor accidents, with no injuries, during 1.7 million miles of driving. “And not once was the self-driving car the cause of the accident,” Urmson noted, though he did not provide any details about the accidents.