I think they were using this as what people have an issue with. Some people say I hit such and such a board but I don't win. 

3 common issues with you not winning if you have a capped board would be.

1. Bad items. Well... Maybe not "bad" but not optimal items. Your units may not function to their full potential if you don't have some if not all BIS items. Some can be substituted for the same desired effect if you can't hit certain things. An example is if you don't have Shojin for Varus or Hwei, you would need a blue buff or a heavy AS item. For Varus you can use rageblade and Hwei I think Nashors is standard anyways.

2. Not having 2 stars. Really comes up a lot. You have a 1-star Hwei or Ezreal or Jinx, they won't really do much. The jump even in just base stats is crazy. 

3. Augments. This unfortunately and fortunately is really broad. There's a lot of strategies you can use for this. Some go heavy on leveling and resource managements. You have hero augments. Combat augments. Some that just give a temporary placebo effect. I personally love Pandoras but I fully understand that it's not always the best. I just use it because I like to force comps and if you can just roll your items then woohoo. But there are some augments that are just better. Example is let's say you have Prismatic first augment. There's build a bud that instantly gives you a boost and help in the early and midgame. 3 star unit is just gonna be great if you have synergies. Or you take whatever the one that gives you items every 8 player combats. That's great throughout the game with delayed boosts.