Pure reactive components are either L or C. Series loss, respectively, is specified as DCR and ESR reduces the quality of reactance, as defined by the impedance ratio Q=X(f)/R
With a series or parallel LC filter, the shape is also defined by Q=fo/Δf for the resonant f =fo and -3dB bandwidth Δf. Depending on the arrangement of series or parallel impedance ratios, it may be a bandpass or bandstop filter, or even HPF or LPF with peaking caused by Q>1.
Generally, when designing a simple passive RLC filter, the steep slope for a very selective application may require a high Q >>1 and the opposite, a smooth phase shift requires low Q <1.
Generally, Q>100 are more difficult to achieve with components or filter designs, but possible but low Q filters with more stages are more stable and reliable.
For many designs, the Q of each component must be higher than the Q of the resulting shape factor. This is also important to improve efficiency, ripple and stability in SMPS.
I did a quick search and found more for you to read. https://www.allaboutcircuits.com/textbook/alternating-current/chpt-6/q-and-bandwidth-resonant-circuit/