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In 1999 John Osher started Dr. John's SpinBrush to sell a $5 electric toothbrush. In 2001, he sold the company to Procter & Gamble for $475 million. Here are his "17 mistakes start-ups make" in 100 words.

  • Failing to spend enough time researching the business idea to see if it's viable.
  • Miscalculating market size. Entrepreneurs say, 'The market size is 50 million people. If I only sell to 2 percent, I'd be selling a million.' But most products sell less than 1 percent.
  • Making a commitment on sales projections that were wrong. Created costs that require those projections to be met. Run out of money.
  • Overprojecting sales prospects.
  • Making cost projections that are too low.
  • Hiring too many people and spending too much.
  • Lacking a contingency plans.
  • Bringing in unnecessary partners.
  • Hiring for convenience rather than skill requirements.
  • Spending half their time doing something that represents 5 percent of their business.
  • Accepting that it's "not possible" too easily.
  • Focusing too much on volume and company size rather than profit.
  • Looking for somebody to tell you you're right.
  • Lacking simplicity.
  • Lacking clarity of your long-term aim and business purpose.
  • Going after too many targets at once.
  • Lacking an exit strategy.

(Photo by juhansonin)