Tensile Stresses:
- Tensile stresses refer to the forces that pull or stretch a material, causing it to elongate.
- The maximum factor of safety is not adopted for tensile stresses in steel structures.
- This is because steel is known for its high tensile strength and is capable of withstanding significant tensile stresses without failing.

Compressive Stresses:
- Compressive stresses refer to the forces that push or squeeze a material, causing it to shorten or compress.
- The maximum factor of safety is not adopted for compressive stresses in steel structures.
- Steel is also known for its high compressive strength and can withstand substantial compressive stresses without failure.

Bending Stresses:
- Bending stresses occur when a force is applied perpendicular to the longitudinal axis of a structural member, causing it to bend or deform.
- The maximum factor of safety is not adopted for bending stresses in steel structures.
- Steel has excellent bending strength and can resist bending stresses well, especially when combined with proper design and reinforcement.

Shear Stresses:
- Shear stresses occur when two forces act parallel to each other but in opposite directions, causing the material to slide or deform.
- The maximum factor of safety is adopted for shear stresses in steel structures.
- Shear stresses can lead to significant structural failure if not properly accounted for.
- Steel is relatively weak in resisting shear stresses compared to its tensile and compressive strengths.
- Therefore, a higher factor of safety is necessary to ensure the structural integrity and safety of steel structures under shear stress conditions.

In conclusion, the maximum factor of safety is adopted for shear stresses in steel structures because steel is relatively weak in resisting shear forces compared to its tensile, compressive, and bending strengths. By using a higher factor of safety, the risk of shear failure can be minimized, ensuring the overall stability and durability of steel structures.