Some ESP8266/ESP8285 modules only work with DOUT SPI flash mode and a SPI flash frequency of 26 MHz. Therefore, these parameters have to be used by default. Otherwise some modules will no boot.
Startup information, including board configuration, is only printed when module esp_log_startup is used. This reduces the amount of information that is printed by default to the console during the startup. The user can enable module esp_log_startup to get the additional startup information.