I MESSED UP! - DON'T make this MISTAKE!

I did the one thing I swore to myself that I would NEVER do. . . I sent a student to a check ride who wasn't qualified and they got turned away.
Anyone who knows me knows I am always extremely diligent and will go the extra mile to make sure my students are knowledgable and prepared before they go to any check ride. 
However, I am still human (I guess) and therefore I am susceptible to mistakes at times. Today I discuss one of the biggest mistakes I've made in recent memory. This mistake cost a lot of time and money and I hope that in sharing this, it helps you avoid doing this same thing in the future!