Whether your current project is classical piano, pop-country, or dubstep, give yourself enough credit to keep your mixes. You may not realize it as you're working, but it isn't uncommon for one of the first few mixes to be the best. For example, Michael Jackson's famous Billie Jean was mixed an astounding 91 times, yet after all of that work, mix number 2 is what made the cut. It's commendable to want to improve and push your limits, but be careful that a desire to improve doesn't transition into doubt over your current skill set.
You can read the full article here, and watch an excerpt of Bruce Swedien's thoughts on the process that went into Billie Jean as well: http://therecordingrevolution.com/2013/02/22/why-your-first-mix-is-likely-your-best-mix/