It is all a matter of your priorities. If your first-priority product attribute is ambitious but achievable, you can usually find a way to get it. But as you increase the number of the second-priority attributes you wish to achieve, you will find it increasingly difficult to meet all of them as well.
One famous computer designer, Seymour Cray, is described thus : ‘He intends not to attempt to exceed engineering limits in more than two areas at the same time because the risk of failure is quite high when you do that.’
Gene Amdahl, another famous computer designer said, ‘What happened with Triology’ (a company he ran that failed) ‘was that the company overevaluated its ability and underevaluated the technical difficulties. It is not impossible to make chips the size Triology wanted, but they wanted in addition to make complicated logic (VLSI) on them. That’s when we got both design and production problems.’