Red is a color with a job. It marks an entrance, signals a threshold, or carries a brand into a space where signage would be too literal. It is used in hospitality and retail far more than in gardens, and that is a fair guide to where it works.
Red is also the color that punishes a cheap finish hardest, because a saturated pigment has the furthest to fade. Jay Scotts note that plastic can “fade, morph, and crack in extreme temperatures” over time. The finish here is an automotive-grade, UV-resistant paint system on a non-porous shell, a coating designed for sun rather than a dye trying to survive it.
Practically: one red planter reads as intent, and several read as a scheme you have to commit to. Against grey stone, dark brick or glass it holds up. Against warm brick or terracotta paving it tends to fight. Related: patio planters, indoor planters and round planters.