Simulated eROSITA-like light curves of a source lying close to either of the two ecliptic poles. These light curves are computed using a typical є evolution, as observed in actual eROSITA light curves. The top panel shows an intrinsically constant source, and the lower panel depicts an intrinsically-variable pink-noise source, both with an average count rate of ≈0.3 cts s⁻¹. The variability class describes how the value of SCATT_LO and AMPL_SIG compares to the variability thresholds computed in Sect. 4. The pink-noise variable source is identified to have a SCATT_LO value above the 3σ threshold but an AMPL_SIG value only above the corresponding 1σ threshold.