whats are the reasons that effective and affordable medical care for everyone is so hard to maintain?

Costs/Socioeconomic status: Many areas have medicine and treatments that are expensive and unaffordable for average citizens. Those in poverty or simply below a specific wage level tend to risk going into more debt with ongoing treatments.
Lack of research and communication: A prime example would be the LGBTQ+ community. With a lack of communication and discrimination towards LGBTQ’s, it is harder to disclose important information and connecting certain diseases to specific groups of people.