People may not be able to actually make or do everything that they can design.
For Grades: 3-5
Learning Goal 1
There is no perfect design. Designs that are best in one respect (safety or ease of use, for example) may be inferior in other ways (cost or appearance). Usually some features must be sacrificed to get others.
Learning Goal 2
Even a good design may fail. Sometimes steps can be taken ahead of time to reduce the likelihood of failure, but it cannot be entirely eliminated.
Learning Goal 3
The solution to one problem may create other problems.