Why did plate armour largely disappear from infantry use in the 18th century?

By the 18th century, plate armour had largely disappeared from infantry use due to a combination of three primary factors:

• Weight: As hand firearms improved in power, armourers were forced to increase the thickness of metal plates to maintain protection. This eventually made the suits so heavy that they became impractical for active service, leading to a preference for increased mobility.12
• Lowered Effectiveness: Advances in weaponry, particularly the development of more powerful muskets, rendered traditional plate armour increasingly ineffective against contemporary battlefield threats.13
• Cost: The expense associated with producing and maintaining high-quality plate armour became difficult to justify given its diminishing utility in the face of evolving military technology and tactics.1

While some elements like breastplates remained in use for specific roles, such as by heavy cavalry cuirassiers, infantry forces largely abandoned personal armour by the 18th century in favor of the mobility and efficiency required for linear formations.13