In my view, good record keeping is a habit that is highly desirable for all investors.
Good record keeping includes not only keeping accurate records of what you have earned, spent and saved and your investments, but also your financial plan and objectives.
Good record keeping serves many useful functions. The most valuable is that putting things down on paper faclitates more objective and reliable review of what hase been achieved - the good and the bad. As an example, preparing and reviewing net worth statements is an invaluable tool in measuring progress towards a goal. It also facilitates the assessment of how well your approach to investing is working (or not as the case may be).
Other reasons for keeping good record keeping include:
1. complying with tax obligations: as someone who recently had a tax return queried, having good records was highly valuable in dealing with the query quickly and confidently;
2. preparing a will: a list of assets and obligations is needed;
3. insurance: having the receipts for the insured property makes this a lot easier;
4. loan applications: having all the documents which a lender is likely to want to see easily accessable can save a lot of time;
5. not missing payments: late charges and penalties are a needless cost;
6. making sure assets are being properly utilised: not managing cash balances is a mistake I made for several years before I realised how much it was costing me.
I would also add confidence to the list. Knowing what my financial position is and how I am progressing towards my goals is a great confidence booster.