Why do so many traditions and religions have saint men who claim having attained enlightenment?

According to the suttas, the then Bodhisatta Gotama discovered by himself that ascetic practices of his contemporary India were not enough (or were even wrong) to attain complete enlightenment. Then, after trying his own methods and intuitions, he reached Nibbana. However, many so-called saint men from other religions and traditions are said to have reached enlightenment in their own terms and according to their own definitions of enlightenment. We even have people within Buddhism itself claiming to have awaken, but still showing signs of craving and unethical behavior. Considering what I've written, why should we deposit our trust, time and effort in the Buddhadhamma, when there are so many other practioners assuring that they have reached their ultimate goals following their own practices? The most common argument for following the teachings of the Buddha is that when put in practice by ourselves we'll see how effective and accurate the teachings, analyses and practices actually are. But the same can be said about most other religions. We have a lot of examples of men and women through history telling stories and personal experiences of feeling the supreme love of god, or attaining Moksha, or becoming one with the Universe, and so on. Can you help me to find new perspectives to solve this problem? Thanks for your time!