Even better: by making mistakes, you will learn!
I love the system of WK because you are not “punished” for your mistakes. If you don’t know an item well enough, you will review it more often until you know it. In the end you will know all items (or at least 98% of them… but that’s totally enough).
@Cancer : if you are anoyed by this little typos, there is something called “userscripts”. These little extensions do extend the funktions of WaniKani.
For example you can show which item will come when in your review pile with the Ultimate Timline Script
Or for your purpose I can advice Double Check. It has many funktions, e.g. to delete a given answer and retype it. ( Of course you should not abuse it by just change everything in the right answer. )
Have fun,
~T 