After an instrument has been assembled, extra components will be found on the work bench.

If your project doesn't work, look for the part that you didn't think was important

Every solution breeds new problems.

Don't force it, get a bigger hammer.

If your project doesn't work, look for the part that you didn't think was important.

The Ninety-Ninety Rule of Project Schedules - the first ninety percent of the task takes ninety percent of the time, and the last ten percent takes the other ninety percent.