So, the basic answer to your question is: a "flat" map projection causes the distortion of land masses due to the allocation of space within it. First, it is important to know that there is only one accurate form of map projection: a globe. However, using a globe (either virtually or physically) can be very inconvenient. The solution is to use a "flat" map. However, the use of this "flat" map comes with the disadvantage of either distorting the shape or size of different land masses, since it is physically impossible to project a round object (land mass) and make it flat without altering its physical characteristics (shape or size).