Exit strategies are rarely mentioned by start-ups, yet they are something every business owner needs if they hope to be acquired, said Geoff Lewis, principal at Founders Fund, a venture capital firm.

Speaking Tuesday at Internet Week in New York, he explained, "entrepreneurs and VCs don't often talk too candidly about how to think about getting acquired, because the best start-ups don't actually sell. The truth of the matter is that the vast majority of start-ups will not IPO, and most start-ups are also not suicidal. They do not want to die. Start-ups do not want to go off into the night with no exit whatsoever." 

There might not be an incentive to plan, as there's nothing to gain for investors, but entrepreneurs don't want to risk running their company into the ground before the deal has been finalized. 

Here are four ways to tell if your company needs a makeover before you try to offload it: 

Your old plan isn't working. Perhaps there is a lack of product-market fit or there's conflict within the team. If you no longer believe in the company's vision, perceive a threat from outside, and have no fundraising traction, you'd better grab a parachute and jump. 

... Or you don't have a plan. If you've finally hit a wall, with no more restarts and pivots, something is definitely wrong. 

Only you see the problems. "Ideally, the outside world thinks that your start-up is doing great," said Lewis. "Preferably crushing it; at minimum, doing OK. People on the outside don't realize the sort of issues or concerns that you have within the company," which might sound good, but could ultimately prove fatal as the cracks begin to show. 

You have enough time. Lewis recommends entrepreneurs give themselves at least six months to plot their way out. Your team should have confidence in you as a leader and be able to work through this time.