The phenomenon of missed opportunities in the course of two scientific revolutions in fundamental physics is investigated: in the quantum relativistic revolution of the first third of the 20th century and in the gauge revolution that led to the creation of a standard model in elementary particle physics (1954-1974). Two cases of missed opportunities related to H. Poincare and his role in the history of the creation of the special theory of relativity are examined on the material of the first revolution. Two other cases of missed opportunities concerning A. Einstein in connection with the theory of the expanding Universe and with failed attempts to build a unified field theory based on a geometric field program are also considered. It is shown that in these cases epistemological and metaphysical outlooks of scientists were in many respects the causes of the «omissions». We mean the conventionalism of Poincare, as well as Einstein’s belief in the stationarity of the Universe and in the incredible power of mathematics as the only creative beginning in the construction of the physical theories. Two similar plots are explored on the material of the second revolution. The first story refers to the Young-Mills’ concept of the gauge fields, which played a key role in the creation of standard model. Several theorists came very close to this concept and, above all, V. Pauli, who for various reasons did not make a decisive step and missed opportunities to associate their names with the theory of gauge fields. Pauli believed that, despite its theoretical attraction, it could not overcome experimentally - empirical difficulties. The second story is related to the quantum field program being rejected in 1950-1960s by most theorists in favor of the phenomenological S-matrix program. As a result, many theorists have missed their opportunities to contribute to the creation of a standard model. And this “omission” was partly motivated by the positivist thesis that in theory only fundamentally observable values should appear. It is emphasized also that the phenomenon of missed opportunities opens the way for the study of the problem of alternative history of science.