Error:Execution failed for task ':app:preDexDebug'.

When using as development, I sometimes encounter this error
Error:Execution failed for task ':app:preDexDebug'.
> ​​com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command 'D:\Program Files\Java\jdk\bin\java.exe'' finished with non-zero exit
value I don’t know. The solution is to add
defaultConfig {
    multiDexEnabled true
} under android in gradle,
but I still don’t know what this attribute is for. Baidu said that it is subcontracting. We all know that the number of android methods is 65k, so here Set whether subcontracting is set to true, but I don't know if this is the right explanation. I hope you can reply me with your opinion. Thank you
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