There is a strategy to getting the fully upgraded event building in every event. It involves making informed and wise choices. Fulfilling all the event quests is only the foundation. If a player wants the fully upgraded main building, they usually cannot also focus on daily prizes. It's almost always one or the other. You'll still get some daily prizes if you focus on the main building and upgrades, but if you focus on the daily prizes you will almost always fail to get the fully upgraded main building.
To maximize event currency, always collect Incidents whenever possible. It's random, but any event currency found this way will help. Also, when spending the event currency, choose the method that prioritizes progress towards the main building and upgrades. In the case of the Forge Bowl, that would have been choosing the players who gained the most yardage per Football cost. And that would have been the lowest value players, which is counterintuitive. Most players will blindly choose the highest value players, mistakenly thinking that the fact that they gain more yards also means they are the most efficient. Also in the case of the Forge Bowl, choosing the Progress Coach whenever using Footballs would have provided that extra push to get more of the grand prizes, which is where the upgrades were. It also makes it easier if you complete at least enough of each event to get the Event Surprise Box, because it always contains a selection kit for the main building in the subsequent event. That's one less upgrade you have to get during the event.
Every event has a different mechanic, but the main thing is to make the choice between the main event building and the daily prizes.
