Building and sustaining personal motivation is tricky business. When you're motivated, you're able to work better, faster, and stay happier while doing it, but when you're unmotivated, you'll lag behind your typical rate of productivity and feel lousy throughout the process. To make things even more complicated, motivation is a wholly subjective feeling--what motivates one person may completely demotivate another, and random feelings or events throughout the day can take your motivation and crush it when you least expect it.

You can't always help your feelings of motivation, but there are certain habits and behaviors that can influence that deep, subjective feeling. Because of this, there may be several ways you're unwittingly compromising your own motivation--these are some of the most common:

1. You're Letting Yourself Get Distracted

Distraction comes in many forms, but there are three kinds of distractions that are particularly destructive to your motivation. The first is the entertaining distraction; you take a "quick break" from work to browse Facebook, and you end up clicking a trail of humorous articles. Before you know it, you're half an hour into reading, and you have no desire to get back to work any time soon.

The second type is the work distraction, and it often comes as a result of having too many tasks on your plate. You shift rapidly from priority to priority without fully accomplishing any one of them. The third type, on a related note, is a communication distraction. You constantly lose focus on your work because you're interrupted by phone calls, emails, and instant messages demanding your attention.

The solution to all of these types of distractions is isolation. If you're interested in preserving or building your motivation for a short period of time, cut yourself off from everything--disconnect your computer from the Internet, turn your phone off, and don't let anything draw you away from your primary focus. You'll find yourself far more inspired to keep working.

2. You Aren't Saying No

It's also easy to feel demotivated when you don't feel in control of a situation. This usually comes down to a problem with saying "no." For example, if you're slammed with work and your boss drops by to leave another massive assignment for you, you might be intimidated to speak up and let him/her know that you're overwhelmed at the moment. Instead, you take on the additional work and mutter to yourself about how busy you are. Alternatively, you could be uncomfortable with performing a specific assignment, but afraid to voice your opinion. You could also be pressured into staying late or working weekends when you don't feel it's appropriate.

In any case, saying "no" from time to time can be valuable in preserving your sense of control in the workplace. You don't have to start rejecting work at every opportunity, but you do have to let your concerns be known and remain unintimidated about expressing your professional needs.

3. You Don't Believe You Can Do This

One of the most common ways people sabotage their own motivation is with a simple belief: the idea that they can't do this. It might be an assignment outside your skillset, a project with an unreasonable deadline, or a task you don't fully understand. If you believe that you can't do something, it's hard to get motivated to do it. In fact, negative thinking and pessimism are proven to be tangibly destructive; if you don't believe you can do something, you actually become less capable of doing it.

To prevent or remedy the effects of this, change your line of thinking. Instead of dwelling on all the reasons why you can't do something, start thinking about all the reasons why you can. Look for support from your co-workers if you have to--just find a reason to convince yourself that you can do this.

4. You're Letting Your Emotions Get in the Way

We've all had bad days get in the way of our work. You wake up feeling exhausted, or you're depressed and you don't know why, or you're angry about something going on in your personal life and it prevents you from focusing fully on work. Unfortunately, most of these emotions can't be helped, but they can be managed and set aside.

Try to separate the source of your emotions from your work environment as much as possible, both physically and mentally. Find appropriate, healthy releases for those negative emotions, and don't be afraid to rely on a support system to help you through those difficult times. A little perspective can go a long way.

5. You're Trying Too Hard

Some people take the blunt approach to productivity; they take on as much work as they can, then work as hard and fast as they can for as long as they can, plugging through breaks and working their fingers to the bone. While at first glance, these types of people seem more productive, this approach can actually ruin your motivation. When you work at this pace, you're highly likely to burn out in a matter of weeks, if not days.

Instead, make sure you have a healthy balance with your work; don't be afraid to take breaks and necessary time to decompress. Even though you'll be spending a few minutes away from the grindstone, you'll have a much better perspective on your work and you'll feel better doing it.