There are lots of truism about poker; the one the occurred to me today was just a simple as the bigger the buy-in, the bigger the stakes then the better the players. That doesn't mean that all the players are on the same level. It doesn't mean that you won't get lucky or unlucky. It doesn't mean you won't have a good run of cards or not.
What the better poker players means is that you will have to outthink, contest more, and risk more to do well. And the higher you go then the worse it gets. People will figure you out if they have you outclassed, if they are a better memory, or if they are better at creating self doubt. If you look around the table and everyone else is more experienced or skillful, then who do you think they are ready to prey on?
So when you are starting out it would be foolish and costly to play at stake with players that are out of your league. It's like trying to play against world class sports players when you started last week. Play at the lowest levels first because that's where you can expect to almost break even.