Watering at midday because that is when you remembered
Midday irrigation loses a large share of the water to evaporation before it reaches the roots, and droplets on foliage under full sun can scorch leaves. The fix is not discipline but automation: a controller or tap timer set to finish its cycle around dawn waters better than any human ever will.
Letting crews over-trim your palms
The carved 'pineapple' look, where healthy green fronds are stripped away, weakens palms, reduces fruit and invites pests. Green fronds are the tree's engine. Instruct any crew to remove only brown and dying fronds and never to cut above the horizontal line of the crown, and be suspicious of anyone who argues.
Buying lush imported plants for a west-facing position
The prettiest plant at the garden centre is often a greenhouse import that has never felt real sun. Placed on a west-facing balcony or bed, it collapses within weeks of warm weather. Ask where stock was grown, favour locally acclimatised and slightly weathered specimens, and match the plant to the exposure rather than to the photo in your head.