Why Repulse was the likeliest battlecruiser to retire

Why was Repulse expected to retire while Hood and Renown stayed in service?

She was the oldest candidate without a major rebuild, while Hood remained potentially valuable and Renown had already received investment that was worth preserving.

Retirement was a resource-allocation decision rather than a judgment that Repulse had no value. By the time she could be released for a major rebuild, newer ships were entering service and the return on the investment was less persuasive. Hood still offered enough capability to justify a planned reconstruction, while Renown had already received an extensive modernization. Repulse was therefore the logical ship to release when the fleet had to choose among three aging battlecruisers rather than rebuild all of them.