Answer: The problem of the hiring organization becoming fixated on a number is to be avoided at all costs. Compensation is a complex topic and how a package is assembled reflects company values and culture.
What a candidate seeks also reflects what s/he values most – e.g. immediate incentives, long term wealth appreciation, family perks and a lucrative educational program. The key is figuring out what your right answer is. Of course, as a starting point, the candidate should have a complete picture of current total compensation and that includes any cash bonus or company contributions that will be distributed at a particular time and potentially lost in a move.
When an HR executive in an organization or a search firm executive is at the early stage of a search, s/he is looking for a number to keep it simple and to determine if you are in the ballpark they have in mind. At this point they are casting a wide net and if you give them a specific number it will be the number they use right up until the offer stage, whether it is accurate or incomplete.
Compensation is not a bullseye on a target it is a complex set of moving figures that reflect your current values, your future compensation and your aspirations.