Hi Ibrahim
This feature is to be used when you can Budget for a project as a whole, except some expense(s) which you are not in a position to estimate
For eg:
1) you import Aluminum for your project and the prices are fluctuating so much so that you cant estimate it.. hence, you can exclude it from the Budget
2) You have enough controls in place to monitor the Procurement and Consumption of materials. but you want to monitor the Labor expenses only
In such cases you can exclude the Material consumption from budget check.. We did this for one of our client
Ajay M