What are the true motives for fasting?

Our relationship with God is very personal and unique. What I use to enhance (or develop) such intimacy may not be the same for others; some people have a very artistic inclination so art becomes their best means to experience God; others love to search deep meanings or find treasures so their explorations to find God is equivalent to others' artistic creations. But what about fasting?

Do we use fasting to remove mountains? Do we use fasting to destroy personal obstacles that block our communication and intimacy with God (such ego, bad habits, temper, etc). Fasting, as I started this blog, is as personal and unique in our relationship with God. but can personal fasting become like an arm twist to God that makes us believe mountains will only be moved if we fast? I remember when they approached Jesus and they asked him why His disciples were not fasting as the religious people had been doing?