“Recalculating…” That’s what the GPS system in your car says when you’ve deviated from the set route. What it’s refraining from saying is: “Dude, you’re not following the plan.”

Wouldn’t it be nice to have something similar when you get off track en route to your goals – when you’re deviating from your game plan for success? If you had a GPS inside your head, here are the “wrong turns” that would set it off:

1. You think it’s “too hard.”

“Maybe I should give up.” That’s what you’re quick to say whenever there’s a setback or things don’t go according to plan: quitting is your default setting. And you rationalize by saying, “I didn’t really want it anyway.”

When you’re mentally tough, you know it’s going to be hard — but it doesn’t matter. Your default is set to persevere. Sure, every once in awhile, you may feel like giving up but that feels even worse so you find a way to bounce back. As Napoleon Hill said: “Persistence is to the character of man as carbon is to steel.”

2. You always have an excuse.

From the transparent (“I’m tired,” “I’m too old”) to the cleverly insidious (“It’s selfish to go to the gym instead of spending time with my family”), our minds are infinitely creative in coming up with reasons why we can’t. (I’m not saying don’t spend time with your family. Just don’t use them as an excuse.) Because guess what, there will always be something.

When you’re mentally tough, however, you’re so focused on your goal and clear on your priorities that potential excuses don’t even register on your radar. And when it truly is bitter cold outside or the room is noisy or the meeting time inconvenient, the mentally tough say: “Great! A chance to prove myself.”

3. Your emotions run the show.

“I don’t feel like it.” “This is boring.” “I’m too upset to concentrate.” If you want to achieve a goal, whether you feel like doing what you have to do is irrelevant. Do you think Olympic athletes “feel like” jumping out of a warm bed at 5:30 a.m. every morning to train?

When you’re mentally tough, you feel the feelings….and do it anyway. So you pick up the phone even though you dread a lukewarm response or outright rejection. You listen to criticism from your boss without getting defensive or lashing out. And, most importantly, you learn to shift your focus from the thoughts that perpetuate the negative emotion – “Why do I always screw up?” – to thoughts that feel better like, “I can do this,” or “I’m getting the hang of this.”

4. You’re reactive, not proactive.

“Why can’t I get a break?” “Why does this always happen to me?” Out of control and up against the world – that’s how you feel when you let external circumstances and the opinions of others dictate your feelings.

When you’re mentally tough, you take responsibility for your thoughts and actions, and you make more decisions: how to spend your time, what to focus on, what’s important and what’s not.

5. You’re fixated on the way things are.

It’s natural to get frustrated when results are slow in coming or you keep running into obstacles: “Maybe it’s not meant to be,” you think. Yes, it’s hard to look beyond the reality that’s in your face everyday but that’s exactly what you have to do.

As sports psychologist Jason Selk says, ask yourself: “What’s one thing I could do differently?” Develop a relentless solutions focus, and don’t take “I don’t know” as an answer. See your current situation as a springboard to what you want, and vividly imagine things the way you want them to be (see how John McEnroe did it here).

When you’re heading from one location to another and you make a wrong turn, you don’t say, “Oh, forget it, I’m never going to get there,” and head back home to the couch. So why would you do it on your journey to your big goals? Get better at recognizing when you’ve gone off track and simply “recalculate” how to get back on.

p.s. For practical techniques to get more mentally tough, get the Mental Toughness For Entrepreneurs e-book. (This is the one with exclusive interviews with New York Times best-selling authors Simon Sinek, entrepreneur coach extraordinaire Pamela Slim, Buffer co-founder Leo Widrig, former Navy SEAL Mark Divine, and other inspiring experts.)