/spreadplayers feedback has some inconsistency compared to scoreboard.

commands.scoreboard.teams.join.success=Added %s player(s) to team %s: %s
commands.scoreboard.teams.join.failure=Could not add %s player(s) to team %s: %s
commands.spreadplayers.spreading.teams=Spreading %s teams %s blocks around %s,%s (min %s blocks apart)
commands.spreadplayers.spreading.players=Spreading %s players %s blocks around %s,%s (min %s blocks apart)

Scoreboard nicely says "player(s)" while spreadplayers says "players" or "teams" even if it only targets 1 player/entity/team

Here's all affected lines:

commands.spreadplayers.spreading.teams=Spreading %s teams %s blocks around %s,%s (min %s blocks apart)
commands.spreadplayers.spreading.players=Spreading %s players %s blocks around %s,%s (min %s blocks apart)
commands.spreadplayers.success.teams=Successfully spread %s teams around %s,%s
commands.spreadplayers.success.players=Successfully spread %s players around %s,%s
commands.spreadplayers.info.players=(Average distance between players is %s blocks apart after %s iterations)
commands.spreadplayers.failure.teams=Could not spread %s teams around %s,%s (too many players for space - try using spread of at most %s)
commands.spreadplayers.failure.players=Could not spread %s players around %s,%s (too many players for space - try using spread of at most %s)

(Lines 1995-1998+2000-2002)

It's a simple fix:

commands.spreadplayers.spreading.teams=Spreading %s team(s) %s blocks around %s,%s (min %s blocks apart)
commands.spreadplayers.spreading.players=Spreading %s player(s) %s blocks around %s,%s (min %s blocks apart)
commands.spreadplayers.success.teams=Successfully spread %s team(s) around %s,%s
commands.spreadplayers.success.players=Successfully spread %s player(s) around %s,%s
commands.spreadplayers.info.players=(Average distance between player(s) is %s blocks apart after %s iterations)
commands.spreadplayers.failure.teams=Could not spread %s team(s) around %s,%s (too many players for space - try using spread of at most %s)
commands.spreadplayers.failure.players=Could not spread %s player(s) around %s,%s (too many players for space - try using spread of at most %s)