Five Reasons to say NO to a job:
1) When you have questions about the people. Life and work is all about people! if you have any questions about the boss or the crew that can't be resolved— whether it's trust or personality issues— you should consider saying NO. Working with the wrong people will make you unhappy a lot faster than doing work you don't like. Remember the old adage: When you lie down with dogs you should expect to get fleas! The opposite is also true: working with good people, you can always learn something!
2) When You don’t have a well-defined title, position, responisbilities, compensation or command structure. If these elemts are not clear before you take the job you're putting yourself into a situation where your success can never be evlauated fairly and/or where you can be jerked around by any number of people. If you're just starting out, have no skills and know nothing, you may not have much to lose and a lot to gain. But for anyone else this could be the bedrock for a bad experience. Always get the details and make a deal you can live with — up front!
3) When you can't do a good job. Life is short and these days, so are jobs! Every job is a stepping stone to a better job, hopefully with more money! Why take a job where you're not confident you can ACE it? if they're offering on-the-job training that may be different, otherwise they're hiring you do be really good at somthing! If you don't think you can measure up, refer them to someone who can. You'll be respected by the employer for your honesty and committment to provide quality services. Equally as important, you will have left the door open for the future.
4) When you would be settling for something less in a growing market. This is a tough one, since no one likes to turn down work. however there are times when you feel there's other opportunities or better circumstances just around the corner. If a job is below you— in standards, prestige or pay— you may grow unhappy quickly and do a lousy job or develop a lousy attitude. Neither is good for you or your reputation.
5) When you've made a commitment you can't or shouldn't break. Sometimes a better offer comes along just a little too late. Depending at what stage of your committment you are at, it may not be a good idea to even try to get out of it. Certainly, at the very least you should find a way to replace yourself with someone equal or better than you to fullfill your committment to the first employer— with no downside for them. Be very careful, however! Even if you don't leave them in the lurch, this will likely leave a very bad taste in their mouth. The result could be a serious ding to your reputation. The better course is to refer someone you trust to take the new employment offer. Even if your referral isn't hired they'll appreciate the favor.