Unpopular opinion: you cant stretch a carpet into a hallway from one end and call it done
Had a guy on a job in Dayton last month who started stretching from the front door and worked his way down a 22 foot hall, then wondered why the whole thing rippled by the time he hit the back bedroom. Carpet has a backing direction and if you fight it instead of working with the stretch, it will find a way to wrinkle no matter how much power you put on it. I checked the power stretcher head and he had it set about a foot short of the wall, so his stretch never actually locked in at the far end. I have seen this exact mistake in maybe 8 houses. How do you all teach the young guys which end to start from, because clearly telling them is not sticking?