Rate My Intuitiveness: Sketch.io

Reviewing Sketch.io and sharing my insights on "What makes a software intuitive?", "What intuitive design?", and "How do you design a software to be intuitive?"
I saw Sketchpad 3.5 on my desktop/ laptop and opened it looking for a sketching app or software that's light and easy (instead of opening Photoshop) for simple sketching task. My "Hot Topic" is "Intuitiveness" and "intuitive design" so I tackled that as I tried Sketch.io.