In the specific case of negative fiscal contingencies, for them to materialize effectively, three consecutive and non-exclusive events must occur: [In this regard, see Alonso Ayala (1998, p. 19).]
1st) In the first place, the tax administration must summon the company to tax inspection, which has a variable percentage of possibilities depending, among many other factors, on the inspection plans that are in progress, on the consistency of the data declared by the company in the different taxes, of the province in which its fiscal domicile is located or in which its activity is carried out, chance, etc.
2º) Assuming that the company has been summoned for inspection, and, therefore, the prescription does not come into play, it must also happen that the tax act in question is discovered by the acting inspector, which also depends on a complex accumulation factors, among which the degree of consistency of the accounting information in general should be highlighted.
3º) Finally, the probability of obtaining success -total or partial- in the eventual defense of the facts discovered before the inspection or before the courts of justice must be studied, for which aspects such as the degree of conformity in the relationships should be studied. taxes, the percentage of resources estimated and not estimated in the different courts for the different taxes, etc. [In this regard, Pastor (1997, pp. 200 and 223-231) can be consulted, who on the subject of tax agreements cites, among others, the reports of the United States and British tax administrations, as well as, in the German case, the empirical works by Kleine (1988) and Ehmche (1997).]