With BTC / USD now in five digits - If you add decimal numbers - bitcoin has become heavy. It is time to consider other methods of measuring cryptocurrency, especially when it comes to portions of money. The average common man can quote the price of 1 BTC, give it or ask them, to calculate the value of a bitcoin 0.001 and their eyes overlap, it is well to be done for the time being
source https://news.bitcoin.com/its-time-to-change-the-way-we-measure-bitcoin/