1. Choosing music that is above their understanding. Many students want to learn their favorite popular piano sheets, but don't realize that these pieces can be quite difficult. The artists who created these pieces have had years of experience and didn't learn in their first week either. It is recommended that students start with easier piano sheets and progress until they can handle more difficult pieces.
2. Choosing piano music that is not challenging enough After mastering easy piano sheets students need to continue to challenge themselves. This is a good point for students to start learning classical sheet music. In order to grow as a pianist one needs to consistently challenge themselves by choosing progressively more difficult pieces.
3. Not practicing enough Practicing can get pretty boring, but if you put in quality practice time the results will pay off dividends in the future. Create a practice schedule and stick to it. If you can't find the motivation to stick with it, it helps to hire a teacher or challenge yourself by finding another pianist to talk to when you get lazy.
4. Practicing too much As odd as it sounds practicing too much can be just as detrimental as not practicing enough. When a student practices too much they often lose focus and therefore the quality of their practicing goes down. The quality of practice is much more important that volume.
5. Not chunking One of the best study forms is chunking. When learning a new piece it is best to break it into chunks. This may simply be two measures or a page, depending on the pianist. However, chunking allows you to focus on mastering the piece one part at a time and makes it less of a daunting task.
6. Setting unrealistic expectations It is not likely that you'll be playing advanced pieces within the first week. Realize that there is a learning curve and it does take time. Therefore make a commitment and stick with it so that you eventually reach your goals!
7. Not identifying their best learning style Everyone has different learning styles that allow them to most efficiently learn skills. These learning styles can also be transferred to the piano. Try to tailor your piano learning to the style that best fits your learning style. For example if you're a visual learner watch videos of others practicing, likewise if you're an audio learner listen to piano music while you're reading the sheets.
8. Being distracted while practicing As mentioned previously, the quality of practice is much more important than the amount of time devoted. This also goes for distractions. Try to devote a certain amount of time without distractions such as television.
9. Not caring / being disinterested If you're heart isn't in playing the piano and if you don't have a passion for playing, gaining the motivation to practice is going to be an uphill struggle. Be honest with yourself and if you truly aren't interested stop wasting your time.
10. Practicing wrong Learning the correct fingering of a piece and practicing the piece through slowly aren't fun tasks, but they're necessary. Many students try to learn a piece too fast and don't master the fundamentals of the piece. Slow down and truly master the piece so that you can play it how it was intended.