A large number of American soccer fields are synthetic, and the surface does not behave like mown grass. A striker who ignores that difference will misjudge the same chance twice.
The ball arrives faster and stays lower
Turf offers less resistance than grass, so a pass slides rather than sits up. The ball reaches the forward sooner and at a flatter height than expected.
That compresses the window for a first touch. A control that would settle nicely on grass runs half a stride further and pushes the striker wide of the angle.
The adjustment is to take the touch across the body rather than in front, letting the extra pace do the work of moving the ball into a shooting position.
The bounce is truer, which cuts both ways
Synthetic fields produce a predictable bounce with none of the divots and soft patches that make a grass surface unreliable late in a season.
For a volleyer that is a gift, because the ball arrives where the eyes said it would and the contact point can be chosen in advance.
For a poacher it removes a source of chaos. Fewer balls skid off a rut past a goalkeeper, so scrappy goals become slightly harder to come by.
Footing changes how a striker can plant
Rubber infill grips differently than soil. The studs designed for grass can catch or slide depending on how worn the field is and how recently it was groomed.
A striker who is uncertain about the plant foot will shorten the swing, and a shortened swing sends the ball toward the near post more often than the far.
Players who spend a season on turf tend to develop a flatter, quicker strike with less backlift, which is a sensible adaptation rather than a technical flaw.
Sliding finishes and stretched contacts get rarer
Going to ground on synthetic turf carries a friction cost that grass does not. Players know it, and they hesitate before committing to a stretching finish.
That hesitation shows up as balls left for a teammate or shepherded out, chances that on grass would have been attacked without a thought.
Coaches can address it by rehearsing the movement on the same surface the team plays on, so the decision is made by habit rather than by caution.
The travel between surfaces is the real problem
American schedules routinely move a team from turf to grass and back within a week. Neither surface is difficult on its own, and the switching is.
Touch calibration takes a session or two to reset, and teams that arrive the night before a game get no chance to make that adjustment.
Which is why finishing form in this country can look erratic without anything having changed in the striker's technique at all.