You cannot have B-level movies, no matter how you define it, without having A-level ones.
A-Level films are often defined by their “important” subject matter, caliber of cast (movie stars and accomplished actors), literary source (adaptations of classics books or plays), prestige and reputation of the director, size of budget, and even release date (Oscar caliber movies tend to be released in late fall, usually November and especially December).
During the studio era, the B-level movie emerged against mainstream Hollywood tradition of glossy illusionism, pomp, earnestness, and pretentiousness.
They tended to be down to earth, low-budgeted, and released in less important (often outcast) movie theaters.
Sometimes, there were the second (bottom) half of a double feature.
Film Theory: Hierarchy of Films (A-List; B-Movie, Definitions)
You cannot have B-level movies, no matter how you define it, without having A-level ones.
A-Level films are often defined by their “important” subject matter, caliber of cast (movie stars and accomplished actors), literary source (adaptations of classics books or plays), prestige and reputation of the director, size of budget, and even release date (Oscar caliber movies tend to be released in late fall, usually November and especially December).
During the studio era, the B-level movie emerged against mainstream Hollywood tradition of glossy illusionism, pomp, earnestness, and pretentiousness.
They tended to be down to earth, low-budgeted, and released in less important (often outcast) movie theaters.
Sometimes, there were the second (bottom) half of a double feature.