Why is it important, for example, when building an excavator, to have a BOM diagram?

And other elements such as LEVELED, MRP and demand fulfillment strategies?

(Explain in an introductory way) (Focused on excavator parts)

#Components: 5 #Operations: 4 # Time Units: 9 # Components: 4 #Operations: 3 #Time Units: 12 3 #Components: 15 #Operations: 12 #Time Units: 12 #Components: 12 #Operations: 6 #Time Units: 6 N3 St 0, GI N4 # Components: 10 #Operations: 8 # Time Units: 12 KI St 10 St 3 [J #Components: 4 #Operations: 3 #Time Units: 9 # Components: 5 #Operations: 4 #Time Units: 8 H3 #Components: 5 #Operations: 4 #Time Units: 7 #Components: 5 #Operations: 4 #Time Units: 10 1N 2 # Components: #Operations: # Time Units: 1 [S] M # Components: #Operations: 5 #Time Units: 9 M2 Level 4 0 1 Level 3 2 3 4 5 Level 2 6 7 8 9 Level 1 B C D E Level 0 A Demand Production Ending Inventory 1000 Excess Short Total Units of Excess Cost for buying product when Short ($) LEVELED 1 2 7000 3000 5040 5040 -960 1080 1080 0 960 0 Quantity Cost ($) 9360 23 3 2500 5040 3620 3620 0 27 Total Units of Short 4 4000 5040 4660 4660 0 Total 16500 20160 9360 960 Quantity 960