Spec has become the short form for any work done on a speculative basis. In other words, any requested work for which a fair and reasonable fee has not been agreed upon, preferably in writing.
In a nutshell, spec requires the designer to invest time and resources with no guarantee of payment.
On the surface it may seem so. But, digging a bit deeper, one realizes that professional graphic design is about creating custom solutions, not cookie-cutter concepts.
This is a common point-of-view for many who confuse the professional with his or her tools. The process is more than simply tapping at a keyboard or clicking a mouse. It’s about understanding the nature of a communication challenge and then using one’s brain to find the appropriate solution.
At the end of the day, there is a certain irony in spec work. A prospect requesting it is ultimately saying, “My project isn’t important enough to hire a professional who will take the time to understand my situation and goals and invest the time needed to create a suitable solution”.