ammonolysisof alkyl halides does not give corresponding amine in pure state?

Ammonolysis of alkyl halides does not give amine in pure state as mixture of amines is formed. First ethanolic ammonia react with alkyl halide to produce primary amine. Now, this primary amine serve as Nucleophile and further react with alkyl halide to form secondary amine which further produces tertiary amine and finally quaternary salt.
R-X  +  NH₃  →  RNH₂  +  HX
​​RNH₂  + R-X  ​→ R₂NHX  +  HX
 R₂NHX  +  R-X ​→  R₃N  +  HX
R₃N  + RX  ​​→ R₄N⁺X-
Hence, a mixture of amines is produced or we can say ammonolysis of alkyla halide does not give amine in pure state.