Noob 3 piece airlock question

Ok i just finished stabilizing and clearing my first batch of wine and have moved on to my second, which is currently in the secondary fermentation phase. When I bought my wine kit the 3 piece airlock I was given did not have the top on it. At the time I had no idea it needed one. So I made that batch of wine without the top of the 3 piece. I did use water to fill the airlock halfway. Could anything negative have happened to my wine as a result? the wine smells fine as of yesterday... additionally my second batch in the secondary fermentation does not have a airlock lid on either, how big of an issue is this? what could possibly happen as a result?

and might it be possible for someone to breifly explain why you need the lid...

thanks

The lid slows evaporation and keeps the middle piece from popping up too far. The airlock should work fine without it. If you are worried, put some tinfoil over it.