The Slow Fade: light deficiency looks identical to nutrient deficiency. Plants yellow, go leggy, stall. Most people add fertilizer. But you can't fertilize your way out of a light problem; measure your PPFD before you do anything else.

The Overcorrection Spiral: wrong diagnosis → intervention → new symptoms → more interventions. The plant is now dealing with three compounding problems you created. Stop everything. Go back to baseline conditions and wait.

The Seasonal Cliff: autumn reduces window light by 60–80% but looks the same to you. The plant declines. You try everything. But your house just got dramatically darker, so measure before you medicate.

The New Environment Failure: a nursery plant drops leaves and looks like it's dying. It isn't dying; it's acclimating from greenhouse conditions to your home. Withhold all interventions for the first three to four weeks.

The Transplant Trap: you repotted and now the plant is worse. Freshly repotted roots can't absorb water efficiently until they reestablish. The fix is counterintuitive; water less, not more, after repotting.

The Fertilizer Rabbit Hole: adding fertilizer to a light-starved plant just builds root zone salt until nutrients lock out entirely. If EC exceeds 3.0 mS/cm, flush immediately, then fix the light first.

The Pest Rebound Cycle: one or two treatments look like they worked, then it's worse than before. A single application never eliminates a population. You need at minimum three treatments at 5–7 day intervals to break the reproductive cycle.