There are a lot of avid collectors that collect Pokemon cards and are also big fans of anything related to Pokemon. Even if they have a lot of Pokemon cards, some of them does not even have an idea on how to actually play them. It does not mean that if you have a huge collection of Pokemon cards that you are already a very good and talented player. In the Pokemon trading card game there are also a lot of things that are needed in order to be a good player. One must know a lot of strategies and how all the features in the game work so that they will be able to know what to do in a game. They must also have rare and strong cards in order to have an advantage over the other players. So how does one know if the cards he has is of value and is useful in the game? There are a lot of mechanics that would determine what are the strengths and weaknesses of the card.
Useful Pokemon cards must be efficient when attacking. It should be able to do a lot of damage but still have a low energy cost so that it would be easy to use and would give a lot of advantage when attacking the enemy player. If it is able to inflict more damage than other Pokemon cards then you could say that, that is a very good card and would be able to help you win a lot of contests. So if you have cards that has a low attacking power and a not so low energy cost then it would be wise if you would just not use it and keep it in your collection.
There are also Pokemon cards that has some bonus features when attacking. Some also have special skills that would greatly benefit you in the game. These cards would be considered rare as it is very useful and would be very effective in a match. They would usually deal a lot of damages or would disable your enemy for a certain amount of time. These cards are very hard to find as there are only a limited amount of them ever made. Since there are rare and hard to find, these cards are very valuable and would cost a lot of money to buy.
The important part in games is that everyone should have fun and should enjoy the game.