The shorter the poem, the more difficult it is to write. Every word must be exactly what you intend to say. There is no time for long winded explanations. Often it may take longer to write a short poem. You are more likely to write it and revise it many times before you feel that each word is perfect and perfectly placed. This may be analogous to a small family. There are not many people so each one much show up. Each one must do their part to create a loving family unit. Every family member must play their role to perfection.