If length is your goal, you should be aware of the factors that affect your hair growth.
Each person has an individual hair cycle growth phase in which their hair has potential to reach its longest. The terminal length of hair is the maximum length that it could possibly reach without being cut or damaged. Hair does not necessarily stop growing once it reaches a specific length but once a certain period of time has passed. The growth phase is largely determined by genetics and typically lasts between two and six years. Most hair grows half an inch per month on average; this can often be faster for Caucasians and Asians and slightly slower for those of African descent. Each hair completes the cycle at different points, so this is the reason most people have multiple lengths of hair on their heads at all times.