What are the challenges that you have faced during test management process?

For me the toughest part to get the top management convinced about the importance of Test process. 
For any process to get implemented, we need approval and support from the management.
Many a times, the time we get for testing is too less as there are delays in developers delivering the qa builds..
In such cases we will have to find out the best way to have maximum test coverage in lesser time and to save the product.
What do you guys think?