Can blockchain lock my funds?

I'm curious to understand more about the potential for blockchain technology to "lock" funds. As an investor in cryptocurrency and digital assets, it's important for me to have a clear grasp of the security features and potential vulnerabilities associated with this technology. Can you elaborate on the mechanisms in place that might prevent or enable funds to be locked on a blockchain network? Are there specific scenarios where funds can become inaccessible, and what steps can be taken to mitigate these risks? Additionally, how do blockchain protocols differ in terms of their ability to safeguard funds and prevent unauthorized access?