Analytical chemists now come to realize this the hard way: Siuzdak and collaborators claim that, in metabolomics, in-source fragments make up over 70% of ions selected for automatic MS/MS and interpreted as if they were intact molecular ions . This causes massive problems for annotation and quantification. All molecular classes are concerned: metabolites , and particularly lipids , nucleosides , N-glycans , modified amino acids (Mamani-Huanca 2020), but also organic pollutants ) and natural compounds ). These recent references illustrate a pressing analytical problem. Internal energy qualification and standardization can be the solution.