slowness
slow-ness
noun
The state or quality of being slow; lack of speed or quickness.
"The slowness of the internet connection was frustrating."
Thesaurus
Synonyms: backwardness, subnormality, mental retardation, retardation, deliberateness, unhurriedness, deliberation, clumsiness, maladroitness, ineptness, awkwardness, ineptitude