Every business owner, with the perspective of time, realizes he or she could have done something smarter -- jumped on an opportunity faster, directed resources at a looming problem sooner, or avoided a bad deal altogether. Here, six smart entrepreneurs, including Nanda Home's Gauri Nanda and Enterprise Rent-A-Car's Andy Taylor, share their biggest regrets.

Gauri Nanda, Nanda Home

My regret: Trying to run the whole thing on my own

When Gauri Nanda started, she had no business plan and no intention of becoming an entrepreneur. But she had a unique product: Clocky, a hybrid robot-alarm clock that rolls around the room beeping when you try to hit snooze. Nanda could have licensed her invention to a larger company but found herself unwilling to hand over control. So she launched Nanda Home, a one-woman business, to bring Clocky to market and to develop other products designed to "humanize technology." Nanda's regret: going it alone. If she were starting out today, she says, "I would try to find more good help from the beginning. I tried to do a little too much myself, and while that's a great way to learn the process and every part of your business, I would have stopped and tried to find one good person to help."

Gary Heavin, Curves

My regret: I said "I" too much

During a long career as an entrepreneur, Curves founder Gary Heavin has had his ups and downs. By the age of 30, he was running his first chain of gyms; a few short years later, he filed for bankruptcy. But hand-in-hand with his wife Diane, who suggested the name for Curves and designed a preliminary version of the logo, Heavin returned to the fitness business, founding the celebrated Waco, Texas-based franchise that is known for its tight-knit community of female members. With his second business, Heavin focused on maintaining low overhead. He also brought a newfound humility to the job of CEO. What does he regret from his early days in business? "I would go back and say 'I' and 'me' less, and 'us' and 'we' more," he told Inc. in 2006.

Andy Taylor, Enterprise Rent-A-Car

My regret: Not tracking customer service sooner

As Enterprise Rent-A-Car approached its fiftieth anniversary, CEO Andy Taylor looked to the future. He worried that concerns about global warming could transform the world's largest fleet of rental cars from an asset to a public relations nightmare. Eager to anticipate and get ahead of the changing attitudes of customers, he spearheaded Enterprise's carbon-offsets program, which allows renters to contribute $1 to environmental projects to offset their carbon emissions. Today, one of the richest men in America says his biggest regret relates to keeping track of his customers' experiences. "In 1996, we implemented a system to measure customer service," he told Inc. "I wish we had done it earlier."

Kevin Rose, Digg

My regret: Dropping out of school

Kevin Rose launched his first Internet business as a University of Nevada freshman, left college his sophomore year, and went to work at a Bay Area start-up. As massive amounts of news began to accumulate online, Rose realized how much time Internet users like himself devoted to sorting and sending each other links, and that what the web needed was a centralized site to share these stories--an insight that became Digg. His regret is academic in nature: "I wish I had finished my computer science degree," he told Inc. in 2008. "Sometimes, I'll be sitting around on a weekend and think, it'd be fun if I could just write up a software app really quickly."

Ken Hendricks, ABC Supply

My regret: Not being upfront with my bankers

Ken Hendricks, the late founder of ABC Supply and a self-made billionaire, started out in the roofing supply business, but he wound up involved in a variety of industries from real estate to industrial art. When the largest employer in his hometown of Beloit, Wisconsin, went belly-up--at the cost of 3,500 jobs--Hendricks bought its headquarters and set about filling them with new businesses, many of which he owned in part or in full. When asked by Inc.'s Leigh Buchanan to identify his biggest regret, he said it had to do with obtaining credit. "I would have shared with the banks my long-term vision and got them involved instead of just going to them when I needed money," he said. "I should have got them on my team right from the start."

Selena Cuffe, Heritage Link Brands

I could say I regret bootstrapping, but'¦

Selena Cuffe is the cofounder and CEO of Heritage Link Brands, a Los Angeles-based importer of wines primarily from indigenous producers in Africa--a company boldly built on the ideal of empowerment and an uncertain supply line stretched halfway around the world. "This is going to sound crazy, but I don't think I would do anything differently," she says. "All the bumps and bruises along the way taught me valuable things about running a business. I could say I regret bootstrapping, but that wouldn't be true. There were a lot of tears along the way, but, especially now, it was worth it."