Flex straight out, through a strain relief connector, can meets specs; needs a smaller hole; & is less likely to fail or cause power loss (while overheating).
Contacts in any power connector will corrode/tarnish with time. A heavy load can bridge corroded surfaces by making temporary micro-spot welds (that then make a good connection). These break when connector removed, leaving more pitted contact surfaces.
UK appliances, with13A plugs, often fail fail PAT testing due to a corroded/tarnished connection. In cordless kettles, it's always the base to kettle connection that fails first.
Cleaning the plug pins with wire wool, or 400 grit paper, then repeatedly plugging & unplugging from socket a few times (to clean socket connections) can help a lot.