Why to say NO in I.T.

This was one of the most important things I first learned in the I.T. field... No is a viable answer!  My first ERP project was a failure at some point because I didn't know how to say NO to management.  Here are some pro's and con's from saying NO in I.T.

Cons- 

1. Employees will start to hate you because you've become the "NO" guy
2. Employees will call you LAZY
3. Employees will doubt your skill set since they don't think you have the ability to deliver
4. Employees will try to hire consultants to take your place when you have the ability to achieve their goals
5. Employees who don't understand I.T. or computers will try to haggle you to saying the magic word "YES" so that they can get what they want.

Pros-

1. You don't give the client a piece of CRAP at the end of the project
2. You let the employees know who's the boss and who really needs who in the organization
3. You take the time to think through if this project is really worth it
4. You don't crash and bring down the production system because of one minion's need 
5. You protect your job.  It's not about how many projects you finished, it's about how many successful products you've delivered that matters to the organization.

Everyone loved me when I was the YES guy at my previous jobs and I loved being the YES guy too because I love taking on challenges and receiving the praises/awards, but the reality is that NO is the best answer sometimes so that you don't screw up the system and regret it.  No doesn't have to mean no, it also means let me figure out an alternative route that will take some planning and time to get this thing done right.