The problem is that many new players buy upgrades without knowing how to use it, just because it's cheaper than buying an action. But buying an upgrade doesn't update your actions automatically, you have to edit actions yourself to include the new upgrade. A pop-up should explain that fact when someone is about to buy an upgrade.
Kalean -- If you look at the Upgrade the description says exactly that.
Phaedreas Tears - 15 years old and first(*) of true neutral guilds in Atys.
(*) This statement is contested, but we are certainly the longest lasting.
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