You may be spending most of your time making design changes
instead of creating new designs. But with the right 3D CAD
software, you can solve this problem – and quite a few others.
If you’re a design engineer working in a “typical” manufacturing company, you may be spending
60% to 80 % of your time updating and optimizing old designs, or making changes for ECOs,
instead of creating new designs. Industry-wide studies and PTC surveys confirm this startling fact.
With such a significant portion of your day devoted to design changes, you need a 3D CAD
system that simplifies and speeds the change process.
But this is just one of many challenges design engineers can solve by using more advanced 3D
CAD software. Here are five essential characteristics of a best-in-class 3D CAD system and how it
will enable you to focus on what you do best: design great products.

From: http://www.ptc.com/WCMS/files/86879/en/3966_Five_Things_EN.pdf