We discussed the right pictures to convey the right design intent for every screen. When ever we cut corners due to lack of time or laziness, we paid the price dearly and confused our colleagues and customers and wasted valuable time during presentations or workshops.
I am not talking about making your prototype pretty and colorful. Even in a skeleton black and white line drawing, I suggest you obsess over the right content in the right place.
We learned that we should rather display a place holder rectangle than put a dummy text or image in the prototype. If you don't have the time put a place holder. But avoid putting dummy content or incorrect content.
Image from www.fusionlab.com