system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why can't our body heal a wound perfectly without forming scars?
gpt
When you get a cut on the arm your body wants to close it as soon as possible so it will stop bleeding and prevent infections. but to do so it needs to fill it with platelet (repair cells) and they begin to "glue" the wound stacking on eachother following a linear pattern (Instead of a regular like the skin) and this makes the visible scar. 

the scar it's a strip of skin that formed quickly and in one verse and thus it's very different from the rest of the skin

think of it like if you are spray-plastering a wall with the spray tool. at some point your ladder falls and "cuts" the freshly plastered wall in a point. you don't have the time to turn on the compressor and the spray tool before the plaster hardens so you decide to just give it a fix with your trowel, making a visible difference in the application of the plaster on that zone

EDIT: some grammar..