The break statement exits the switch immediately. I'll show you: when a case matches and runs its code, break jumps to the closing brace of the switch. You need break after each case or the program continues to the next case's code.
This is rarely what you want, so almost every case ends with break. Forgetting break is a common bug. If case 1 has no break, its code runs, then case 2's code also runs. Both cases execute when only one should.