Visualize 'inch by inch' as a slow, steady movement, representing determination and progress over time. He is climbing the career ladder inch by inch, showing resilience.
Pro Tip 2/3
Not Instant
'Inch by inch' implies that progress is not immediate; it takes continuous effort to see results. I'm learning the guitar inch by inch; I can't rush it.
Pro Tip 3/3
Physical Distance
'Inch by inch' can also literally mean moving in very small increments, often implying a tense situation. The climbers ascended the mountain inch by inch, avoiding any sudden movements.