Why does the elementUI NavMenu component defaultActive method execute multiple times when the page is loaded?

Hello, everyone
I use vue+elementUI+webstorm to develop web navigation bar
I bind to el-menu: default-active method
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this defaultActive method I just defined in method, not in the hook function, why is the page loaded so many times? Under what circumstances will the defaultActive method be executed?

Mar.11,2021
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