Sometimes, you can make a counter-game try in response to a game try. If South had: 

 K32  
 KQ982  
 876  
 43, 

with the same auction, they could try 3 to say "Partner, I'm not sure, but I have something in hearts." This type of counter-try is useful and it's why if you have two suits where you might use help, you should bid the lower one so that partner might highlight strength in the other suit. 

Notice how much easier these game tries can make our bidding decision. We still can "accept" an invitation with great hands or "reject" (by returning to our suit on the 3-level) with a minimum. The in-between hands become much easier to judge using Help Suit Game Tries. 

It's good to play these bids even in competition. With an auction like: 

West	North	East	South
			1
1	2	2	?

, South should bid 3 or 3 to invite game. 3 is purely competitive. This agreement makes it much easier to avoid accidentally bidding to game instead of simply pushing up the level of the bidding.