Tracks are chosen so that the judge or steward can easily determine where the track is located, and where articles are to be placed, even after the marks, ribbons, or flags have been removed.

Finally, individual errors in pitch track are corrected by a smoothing method, in which a searching and tentative method together with a judge mechanism of adding or eliminating pitch period is used.

The project manager may, however, want to track appropriate measures of requirements volatility to judge whether new or revised (75) are necessary.