The leading diagonal pattern is very similar to the ending one. It consists of five sub-waves, labeled 1-2-3-4-5. Its first wave is usually the longest, while the third wave cannot be the shortest among waves 1, 3 and 5, and waves 2 and 4 are always corrective. Waves 1 and 4 should overlap. There are, however, few notable exceptions. First, leading diagonals occur in the position of the first wave within a regular five-wave impulse or in the position of wave A of a simple zig-zag correction. Second, unlike ending diagonals, where each of the five waves is corrective in nature, the structure of the three motive waves of the leading diagonal – 1, 3 and 5 – can be corrective as well as impulsive.