Definition of "maddeningly"

Hardman ran to the corner and jumped into a trishaw. The driver was maddeningly slow and stupid.

1958, Anthony Burgess, The Enemy in the Blanket (The Malayan Trilogy), published 1972, page 378

Precise herbed-lamb packets amid art nouveau swirls of asparagus noodles, a lacy tuile that adds a peekaboo seductivity to potato gnocchi — [Anthony] Martin’s presentations are bold and beautiful, yet his flavor pairings are almost maddeningly subtle, driving overanalytical foodies to despair.

2011 January 13, Phil Vettel, “Chef of the Year: Anthomy Martin”, in Chicago Tribune, 164th year, number 13, section 5, page 4

Using her hands like windshield wipers, she tried to flick snow away from her mouth. When she clawed at her chest and neck, the crumbs maddeningly slid back onto her face. She grew claustrophobic.

2012, John Branch, “Snow Fall : The Avalanche at Tunnel Creek”, in New York Times‎