Stress, how do you handle it?

Very often I have customers asked me: I have too many green plants, can I buy those pink, red and purple colour plants in your picture?
Not many succulent plants are naturally born pink and red, like Romeo Rubin, most turn pink and red because they are stressed. What is stress? To make it simple, you can understand this way:
A succulent plant will become colourful when it's hungry ( lack of fertilizer), thirsty ( too much sun, not enough water), and cold ( temperature drop).
When the plants have adequate nutrition and water, they will keep growing in size, have you noticed after a few days of heavy rain, your plants are double in size but also as green as vegetables? That’s reason succulent plants in pots are easier to get the colour than those in the garden bed, as in the garden bed, it’s hard to control the water. Well-drained soil in pot, full sun, proper control of watering are the key elements to make your plants stress so they give the colour you are after. There are a few things you need to know:
1) Do not stress young plant, let it grow to the size you want, you only stress mature plants which healthy enough to handle the harsh living condition.
2) Do not stress your plant after re-pot. Put it somewhere with morning sun or filter sun for 2-3 weeks until it settles in it’s new pot. I don’t buy stressed plant online. When the plant looks so colourful in the picture, it has been stressed, but take it out of pot, post, re-pot, which will stress it more, just too vulnerable. I’d rather buy those green ugly duckling and stress it myself.
3) It takes time to stress the colour out of your plant, it needs 3-6 months to develop a healthy rooting system, for those who look after their plants day in and day out, will understand why it’s an emotional thing when you sold your plants.

These 2 plants in the picture are exact same plants ( Echeveria Laulensis), one is stressed, one is not, don't you think it's fun to grow succulents?