Sukura invented Microns as an inexpensive and diposable alternative to high-priced technical pens. The micron are best used on paper. The nibs are essentially "micro size plastic tubes" which allow pigment ink to easily flow from barrel to paper. If a foreign matter clogs tubes, the ink gets blocked.
Microns are designed to held at a 90 degree angle (like a technical pen), not a normal writing implement. Also, they need to be used with a very light touch. You will know if you are holding too tight if your hand cramps or the nib bends/breaks off. You can help this by switching to a thicker nib size (instead of 01 try a 05) and using lighter hand pressure when drawing.