You pay the bonus to the whole team only if you win the match.
Is good, by my viewpoint, game have matches with better or worst scenario, and it helps to give stability to more % of matches.
Is like if you play all season with 50% of condition or 100%.
With 50% maybe you will win a lot but in some punctual cases teh differance will overcome you and the condition will make this slightly differance that can help, bonus is just the sam, one of these little multiple things that affect the matches.