why cant most stis be transmitted through casual contact with people or contaminated objects?

why cant most stis be transmitted through casual contact with people or contaminated objects?
Answer
Brief Explanations:
Most STIs are caused by pathogens that require specific body - fluids and mucous membranes for transmission. Casual contact or contact with contaminated objects doesn't usually provide the necessary conditions like direct access to mucous membranes or exchange of relevant body - fluids for the pathogens to survive and infect.
Answer:
Most STIs are caused by pathogens that need specific body - fluids and access to mucous membranes for transmission, which casual contact or contact with contaminated objects typically does not provide.