Something that a lot of new players first start to discover is what starting hands to play in early/middle/
late position. There are at least a dozen starting hand charts floating around on this site alone. As a result, players new to
NLHE have a decent preflop game in comparison to other
microstakes players. However, a lot of these players get frustrated because of players calling their raises with hands like A5s, flopping
two pair against their
top pair top kicker, and taking a good portion of their
stack. They
don't know how to play against players who are making such apparently terrible decisions preflop because they can't decide if their opponent has
bottom pair or
middle set.
Without knowingly doing so, these opponents have bypassed our new
hero's preflop preparation and are taking the game into a place that these new players aren't as prepared for. The same thing happens when our
hero learns how to c-bet, but his opponents start floating him left and right.
Hero has been taken out of what he knows how to
deal with and is forced to play a game he doesn't know so
well.
Perhaps this doesn't have so much application in poker, but for new players it can definitely be a lesson of why you should learn to play
well on all streets instead of just preflop and on the
flop.