In games like chess it is instructive to find out what your opponent is trying to do. What, if any, threats their moves carry and their overall plan! After that then you can think about your own plan and the moves that contribute to that plan. If you get this the other way around then you will fall foul of simple tactics and combinations. In short then this is what a novice player does or even an advanced novice.
They have yet to train themselves to look for potential threats first and foremost and is why they lose so often and so quickly. The poker equivalent of that is the player that simply looks at their own cards and the board and then makes a decision without looking at any other underlying factors. In poker then your opponents will also have a plan. This may be something deep like an overall strategy but more often than not it is a plan for this hand only.
However the better players will also notice what their opponents are doing much more and change the way that they play. Chess grandmasters do this when they change their openings. If they played the same opening all the time then not only would they be readable but it would be very easy for their opponents to prepare against them. Against sophisticated opponents then you absolutely need to adjust how you play and this is important.
You will often hear many poker players discuss the merits of “changing gears”. This is a phrase given to a way of playing poker where you adjust the “speed” of your play. You may for example go onto a table and play very aggressively for the first ten minutes of so. When you do this against very good players then they will adjust. Their adjustments could be 3/betting you more often or 4/betting you more often pre-flop and calling down more often when you fire multiple barrels.
Whatever the reason then good players will adjust to you and this is the primary reason as to why decent solid poker players struggle when they play higher level poker. Suddenly their opponents are no longer just playing their own cards but making correct adjustments in many cases against what you are doing. If they suspect a weakness in any part of your game then they will attack it. If you are too defensive then they will attack that weakness. Likewise if you are too aggressive then they will find ways to use your own aggression levels against you.
Poker becomes an entirely different game when you go up against sophisticated players but this is the fascination of the game for many people. Your opponents will have an agenda and an underlying plan for how they want to operate. When you can find out what that is then not only will you be one step ahead of them but you will be in a position to own them in many instances.