Gardeners have failed to turn up

Dear Sir, — I have a need for some serious garden maintenance and wonder what I am doing wrong? 
I have responded to three different businesses that have advertised in your newspaper and on each occasion, having agreed a time for them to visit, the individuals concerned have failed to appear. On a fourth occasion, the individual concerned did arrive, agreed the level of work and went away to determine a price “I’ll be in touch” — I heard nothing.
I am puzzled as to why, if they feel the need to advertise together with its cost, do they then abuse potential customers in this way. There may, of course, be extenuating circumstances that result in failure to appear but surely a quick telephone call would go some distance to ensuring the future wellbeing of their businesses.
Can anyone throw some light on the situation for me please? — Yours faithfully,