Part of the reason that double-entry bookkeeping works the way it does is to provide error-checking (remember: it originated when everything was written by hand in large ledger books and added-up manually). As the Wikipedia entry for Double-entry bookkeeping system says in its introduction:
The accounting equation is an error detection tool; if at any point the sum of debits for all accounts does not equal the corresponding sum of credits for all accounts, an error has occurred.
while noting that passing this test doesn't guarantee there are no errors: it's just one way to detect some of the more common ones. Later, it expands on this point:
Recording of a debit amount to one or more accounts and an equal credit amount to one or more accounts results in total debits being equal to total credits when considering all accounts in the general ledger. If the accounting entries are recorded without error, the aggregate balance of all accounts having Debit balances will be equal to the aggregate balance of all accounts having Credit balances.
The point is that if you record that your salary came from somewhere (before arriving in your bank account), then at any point, you can "add everything up" and you should get to zero (if you regard either debits or credits as negative): if you don't get to zero, then there definitely is an error somewhere in the accounts.
If you didn't bother to record that your salary "came from somewhere", then the books will never balance, even if everything else is correctly recorded. But that also means you cannot tell if things have been incorrectly recorded.
For personal finances, if you don't want to be bothered keeping a detailed account of where money came from (salary, gifts, etc.), nor specifically where your money went (clothes, food, rent, etc.) then you could simply have a single "World" account: anytime you spend or receive money, you make a balancing entry against it. It will keep the overall figures in agreement without having to track every little detail.