Final answer:
Adjusting clipper or trimmer blades flush can lead to skin irritation or cuts, as they may pinch or snag the skin during use. It is vital to maintain a precise gap between the blades for safe and effective hair cutting.
Step-by-step explanation:
Clipper or trimmer blades should never be adjusted flush to each other because doing so can cause skin irritation or even more severe skin cuts. When the blades are set too close together, they can pinch or snag the skin, leading to discomfort and possible injury during use. Clippers and trimmers are designed to effectively cut hair with a precise gap between the blades to ensure safety and a clean cut. Regular maintenance, including proper blade adjustment and oiling, is essential to keep these tools functioning safely and effectively.