Fire Pokemon are all about power, but for a cost. Many of the more powerful attacks require you to discard energy. A perfect example would be Blaine's Charizard. His first, quite confusing, attack requires you to discard all fire energies attached to it. Your first reaction is to forget about it then your read on. The attack pretty much states that all fire energy you discard will be treated like 2 fire energy. The attack will do 20 damage, plus 20 more damage in this way.
So if you discard 1 fire energy, it will do a whopping, 40 damage!!! That's an incredible amount for just one energy. Another example is any Pokemon that has ember, like charmander. Discard 1 energy for 30 damage. Does good damage yet you have to discard energy. What I'm getting at here is that the fire Pokemon tech, is to have a great amount of power yet requiring you to discard energy.
Another little thing about fire Pokemon, is they very rarely attack anyone except the defending Pokemon. That means, they don't usually hurt themselves or the opponents bench Pokemon. They focus completely on destroying the Pokemon in front of their face. Lets look over this again and look at the MAIN tendancies of fire Pokemon
:::They don't hurt themselves
:::They don't hurt the defending Pokemons benched
:::They usually require discarding energies for gruesome attacks.
There you go