What are the cons of immutable?

Could you elaborate on the disadvantages of immutability in the context of cryptocurrencies and blockchain technology? I'm particularly interested in understanding the potential downsides in terms of flexibility, error correction, and scalability. How might immutability limit the adaptability and evolution of these systems, and what challenges does it pose for developers and users alike? Additionally, could you discuss any potential security concerns or vulnerabilities that may arise due to the immutable nature of these systems?