Why weren't the Czechs invited to take part in the Munich Conference?

Basically, the French and the British did not allow the
Czechs to have a representative at the Munich Conference because they were afraid that
the Czechs would ruin the deal that they wanted to make with Hitler.  The French and the
British had no desire to fight for Czechoslovakia.  They wanted to make a deal in which
they would give the country to Hitler rather than
fighting.

If that was their goal, there was no way they
wanted the Czechs at the conference.  The Czech government would never have agreed to be
given to Germany.  They would have raised a fuss and maybe caused the whole deal to fall
through.  France and England did not want that at all.

So
the French and the English excluded the Czechs because they did not want the Czechs to
ruin the deal they were going to make.