Likewise using local variables instead of global variables. The point of structured programming is that it's less flexible than gotos are. Decreasing the flex

Likewise using local variables instead of global variables. The point of structured programming is that it's less flexible than gotos are. Decreasing the flexibility of programming constructs means that the reader has fewer possibilities to consider and hence makes the result easier to reason about. Beyond structured programming you might have object oriented programming that uses restricted access to the object's members to enforce certain parities on them that make the object's behavior easier to reason about. Or functional programs that restrict the persistent mutable state and make programs easier to reason about in another way.