Control Structures and Complexity
One reason so much attention has been paid to control structures is that they are a big contributor to overall program complexity. Poor use of control structures increases complexity; good use decreases it.
One measure of "programming complexity" is the number of mental objects you have to keep in mind simultaneously in order to understand a program. This mental juggling act is one of the most difficult aspects of programming and is the reason programming requires more concentration than other activities. It's the reason programmers get upset about "quick interruptions"—such interruptions are tantamount to asking a juggler to keep three balls in the air and hold your groceries at the same time.
Make things as simple ...