AThe choice is determined by floor surface, not preference. On commercial carpet, use standard hard casters — they roll smoothly and carpet prevents scratching. On hardwood, tile, or LVT (luxury vinyl tile), use glides (stationary feet) or soft polyurethane casters — hard casters on hard floors scratch the surface and roll uncontrollably, preventing chairs from staying in position during meetings. On polished concrete, specify soft polyurethane casters — hard casters damage concrete and glides are nearly immovable. If the conference room has mixed flooring (carpet in the center, hard floor at the perimeter), soft polyurethane casters are the safest choice for both surfaces.