Index funds vs active management vs individual stock picking, and why costs and turnover matter for long-term results.
Passive index funds track a market at very low cost; active funds try to beat it but charge more and often underperform after fees. Most beginners use low-cost index funds as a core, adding anything active only as a deliberate satellite.
A passive index fund seeks to track a published benchmark — for example a global or S&P 500 index — holding the index’s constituents so your return closely matches the market minus a small fee. An active fund employs managers who select securities to try to beat a benchmark. Individual stock picking is doing that selection yourself.
The trade-off is cost and dispersion of outcomes. Index funds are cheap and predictable relative to their benchmark; active strategies carry higher fees, higher turnover, and a wide range of possible results — some beat the market, many do not.
Fees compound against you. A fund charging 1.5% versus 0.1% surrenders about 1.4% of your balance every year, which over decades can consume a large fraction of your growth. High turnover also generates trading costs and, outside NISA, taxable events. Because the average active fund holds roughly the market before costs, subtracting higher fees is why many underperform their benchmark over long horizons.
This is not a claim that active management can never work — some funds do beat their index — but that identifying them in advance is hard, and the cost drag is a reliable headwind. For a core holding, a transparent low-cost index fund is the simpler, cheaper default.
Active choices can be reasonable as a deliberate, limited "satellite" — for exposures an index does not capture, or a strategy you understand and want. The discipline is to keep the bulk of the portfolio in a low-cost index "core" and cap the active or single-stock sleeve at a size whose failure you could absorb.
The most common beginner mistake is the reverse: selecting funds by last year’s return and ending up with a scattered collection of overlapping, expensive, actively chosen products. Decide the core first; treat everything else as an intentional exception.
Brokerage (NISA/iDeCo) · Rakuten Securities
A leading low-cost brokerage for NISA and index-fund investing, integrated with Rakuten points and Rakuten Bank.
Fees: Many domestic funds and trades are low- or no-commission — verify current fee schedule.
Brokerage (NISA/iDeCo) · SBI Securities
Japan’s largest online brokerage by accounts, with a very broad low-cost fund lineup and full NISA/iDeCo support.
Fees: Many trades and funds are low- or no-commission — verify current fee schedule.
Brokerage (NISA/iDeCo) · Monex
An established online brokerage often chosen for US-stock access and research tools, with NISA and iDeCo support.
Fees: Commissions vary by product; some funds/trades are low-cost — verify current schedule.
This is education, not a recommendation. Most beginners research low-cost, broadly diversified index funds — for example all-country (全世界株式) or S&P 500 trackers — rather than picking individual stocks, because low fees and diversification are within your control while returns are not. Understand that values fall as well as rise, match the risk to your time horizon, and never invest money you may need soon.