A Tracer is not an investment fund. In a fund, there is discretionary management, you entrust your money to the manager who invests according to the fund's management policy and its analyses. In this case, it is you who keeps the decision to invest in each of the targets which are selected only on the basis of a set of objective criteria.
By the effect of this right of withdrawal, the portfolio of the investors committing to invest in a Tracer can be different from the portfolio of all the other investors having subscribed to this Tracer.