the blinds are more spaced on the 9-player tables, On a full ring table, you will have to post 1.5 BB every 10 hands, while on a short handed table, you will post 2.5 BB every 10 hands. This represents a 66% increase, which will greatly influence your game. On a full ring table, players can play a lot less hands without having a direct negative effect on your share of gain or loss.
The more players there are, the more you have to play carefully
It is very important for a player to take into account, in his strategy, the number of his gaming partners present around the table.
the game 6max requires more quality postflop (forcibly you get back more shots). the more the number of opponents will decrease at the table, the more your hand will take value.On a 6-max table, you will have to play way more aggressive while in full ring you can afford to wait and wait for a good hand.
Even though the majority of players have made their debut playing on "full ring" tables (complete table with 9-10 players), most players then tend to opt for 6-max tables.