On a whim, I just created a wallet. I put a very small amt of $ in it. And within 3 seconds, it was emptied out.
I know this is not ground breaking knowledge, but it is first hand:
What this is teaching me:
The people who crack your keys are not specifically targeting your wallet. However, you can just picture someone with a dictionary of wallets (in programming terms, a dictionary is just a list of predetermined words/sets). And the hackers just have a algorhythm continuously monitoring a large number of wallets. As soon as an unsuspecting person puts money in an otherwise empty wallet (i.e.: I looked at the wallet and it was empty before I used it), boom, the money will get emptied out.
As time goes on, that dictionary of wallet will grow larger and more complete. This means even if you use a long phrase, chances of that phrase (say, "four scores and seven years ago") will be part of some dictionary. So, I am going to avoid any sentence phrases like that.
I know that this post is nothing new to the experienced btc'er but it is my own experience and I am learning it first hand.