Definition of fancy play syndrome
This syndrome is also referred to as FPS. What is meant by "fancy play syndrome" is playing in an unnecessarily distinguished way. Sometimes the best way to play your hand is in the classic way. You have a big hand and there is a draw, you bet hoping to get called by a worse hand; bet, bet, bet. A player with SPF might for example bet 1 big blind, plus raise an unconventional amount or check flop + turn to overbet the river. The examples are numerous. SPF is the opposite of a solid ABC poker.
The problem of the fancy play syndrome
Often, playing in a "fancy" way will make us lose money because your opponent will suspect something. This is called FPS especially when you have a good hand. Some players will pass the flop and turn with a very strong hand instead of betting. The consequence of this is that instead of getting paid when their opponent has a good hand, they will just give their opponent free cards. Experience the fancy play syndrom, especially if you are a beginner. Go with a good old solid ABC poker.