Answer :
To answer this question, first we must star in the question "why do we need to keep financial records"? and the answer for that is for backup to a tax issue or a proof like you di something like a payment. So why do we clean them? Because some documents are unnecessary like your IRAs, 401(k)s and other retirement accounts don’t qualify for capital gains tax treatment, so there’s no need to keep track of what investments you bought. In some documents you just need to keep is the summary. For example, you can discard pay stubs once you get your W-2 and compare it to the summary on your year-end pay stub.
One correct reason is:
We do not need to keep every financial document we receive. For tax purposes, comparing the amounts on your W2 form to those on your end of year pay stub would suffice to ensure the information is correct instead of keeping every pay stub from the year.
Some people keep a copy of bills they have paid; after a couple of years, it is safe to assume that there are no problems with your payments and you can discard those copies.
The same is true of your bank statements; after 3 to 5 years, most people throw away old statements. After that much time has passed, if no problems have arisen, it is not likely for one to arise.
If we were to keep every piece of financial information we receive, we would run out of space to keep them. We need to do an occasional purge of these records in order to decrease clutter.