Answer:
it prevents all sleeper or hideout plays and prevents a shift from occurring.
Step-by-step explanation:
I inferred this question is referring to flag football game rules. Interestingly, flag football unlike other sports requires a team of seven players with a minimum of 5 to continue a game.
By allowing seven men on the line of scrimmage prevented hideout plays from unknown players, and since only one offensive player could be in motion it also prevented a shift from occurring.