The ‘any two suited cards’ is a very popular hand that all varieties of beginners like to play.
A flush is a pretty strong hand in the game of Holdem, and so if you manage to
make one there is good chance that you will win a nice bit of money with it.
Therefore many new players to the game will be prepared to enter pots
with any two cards as long as they are suited just in an attempt to catch a flush at
some point during the hand.
There are two reasons as to why playing any two suited cards is dangerous.

Firstly, it is not that much more likely that you will make a flush just because your cards
are suited.
The probability of making a flush in Holdem is pretty low, and so it does not justify
calling bet and raises in an attempt to catch one on the flop.
On top of this, amateur players will often continue to call bets and raises with
bad pot odds to make a flush on future streets, which just adds to the problem of
playing such hands.
The second reason is that you can catch half a hand like second pair on the flop,
and end up losing money to another player that has formed a better pair than you.
So by playing random suited cards you are setting yourself up for two great
opportunities to leak money, so don’t do it.

Another type of hand that always manages to cause the beginner poker players a
problem is the low connecting cards.
These are almost identical to the problems caused by any two suited cards and
can help players to lose money over the long run.
It is not too likely that you will form a straight every time you enter a pot with
connecting cards like 5c 6h, so don’t enter the pot under the false pretences that you will.
You will simply be losing more money in the long run, as well as losing money in
pots where you catch half a hand and your opponent catches a stronger one.
So save yourself some money and fold before the flop.