Performing enough feats of heroism to be promoted to the next rank
Heroics or the act of being heroic is supposed to be the primary goal of all heroes, but it is also one of the main methods in which a member of the Hero Association can be promoted in ranks.
Due to the corporate nature of the Hero Association and its commercialized heroes, crimefighting and rescues are now seen as tools to advance oneself. Heroics are seen as the most cost-effective methods of being promoted, which therefore brings publicity to a hero's company. As a result, the altruism that normally came with such acts is no longer a driving factor to performing such feats. Therefore, people such as Ankaiser now see the role of being a 'commerical hero' as no different as a regular person holding down a steady job. It's all just business.
Since the creation of the Hero Association and the proliferation of 'heroes,' the crime rate has dramatically reduced. However, this in turn has caused a lot of infighting and stiff competition between the heroes to vie for the most publicity and so-called good deeds in order to get promoted to the next rank. This can lead to public endangerment and there are some who may use underhanded means to look more like a hero, (such as Ankaiser turning off the Grand Carrera hotel's sprinkler system so he'd look more heroic when he captured Ratman). There's even a Hero Awards Ceremony held every year, in which the best of these heroes are celebrated. As a result, many heroes are considered as nothing more than selfish and glory-hungry individuals. In Crea Mizushima's opinion, they are not true heroes but mere tools for their corporate sponsors.
The rate in which a hero is promoted can be directly proportional to how many feats of heroism he/she performs in a given period of time. For the hero IS-KA, he most likely set a record of being promoted from D-Rank to B-Rank in just under a month. However, his rapid rise through the ranks is also one of the main factors which led to the other heroes run amok with the Hero Booster Program .
Of course, there are exceptions such as Randolman and the Akiba Holy Girls, who still believe in the true meaning of being a hero and want to help the public for the greater good. Despite being a so-called 'villain,' Shuto also believes in true heroism and continues to do heroic deeds, despite knowing that he may never get a Hero's License. Then again, after hearing how callous Ankaiser's comment was about heroes dying the moment they sign up for corportations, Shuto had decided that getting a license was not worth it.