Thinking about quitting your job but can’t quite commit? Bestselling management author and CNBC contributor Suzy Welch reveals the one secret about quitting that no one ever tells you, and “it just might help you make your decision today.”

“About six weeks after you quit, if not sooner, you’re going to realize that you waited about six months too long to walk out the door,” Welch tells CNBC Make It. You’ll realize that all your reasons for hesitating were unfounded. “Your life is going to go on — only better.”

Welch says that while the realization that you waited too long might not hit everyone like a lightening bolt, in her experience, it does roughly 90 percent of the time. “That next job you thought might not happen? It does,” she says. “Your former coworkers hating you? They don’t. The company collapsing without you? It won’t.”

Chances are, if you’re spending that much time contemplating what might happen if you leave your job, you’re no longer truly engaged with it, and you have a clear indication of what you should do. “If you’re thinking about quitting all the time,” says Welch, “you already know what you need to know. It’s time for you to go find a better fit, face exciting challenges and grow in new ways.”

The decision to quit your job is one that carries big consequences, of course. “There’s money to worry about,” says Welch, “and your resume, and your reputation.” But, she emphasizes, “don’t underestimate your resilience or your worth.”

Once you realize it’s time to quit, don’t waste any more time weighing the pros and cons — go out and find the next challenge.

“Have the courage to believe in yourself and your future,” she says. “Most of the time — and I mean most of the time — the only thing you’ll ever regret after making the leap is how long you took to do it.”