When investors sell funds, they will charge the fund redemption fee according to the holding time. For example, if an investor buys a 2,000-yuan stock fund and holds it for less than 7 days, and the fund company charges a handling fee of 1.5%, then the calculation formula is: 2000 * 1.5% = 30 yuan, and this 30 yuan handling fee is deducted when the fund is redeemed.

Therefore, when the fund bought by investors has no profit or loss, it is necessary to deduct the handling fee. After deducting the handling fee, the foundation will pay the principal at a loss.

If the fund is in a loss state, it will lose more besides deducting the loss money and 30 yuan handling fee, so when the fund is redeemed, it will also lose money to the principal, so when buying the fund, it must buy low and sell high, so that the money earned can offset the handling fee and will not lose money to the principal.

It is worth noting that when investors redeem funds, they may encounter delays in collecting handling fees. It is possible that the procedures of the previous trading day will be included in the profits and losses of the next trading day, so some investors will feel that the fund redemption will lose the principal.