Why do we say welcome?

Could you elaborate on the significance of saying "welcome" in various contexts? Does it simply serve as a polite greeting, or does it convey a deeper message of hospitality, inclusivity, or a sense of belonging? How might the tone and intention behind "welcome" differ in a formal setting, such as a business meeting, versus a casual gathering with friends? And, in the realm of cryptocurrency and finance, does the use of "welcome" play a role in fostering a sense of trust and collaboration among industry professionals?