First, there were a lot of run-down apartment buildings. Emphasis on "run down" and "a lot," and interspersed throughout the city. Yes, Egypt isn't the richest country in the world, but it's still a large (read: more than 20 million) city and prevalence of poor buildings was surprising in all areas of the city.
Second, there seemed to be a preponderance of unfinished buildings. This isn't entirely uncommon in Muslim areas but, again, Cairo is a large city and, once more, there was surprising amount of (seemingly non-progressing) construction.
Things like this don't happen without reason; where there's bizarre outcomes, government nonsense isn't usually too far behind. See if you can guess for yourself the government policies that exaggerate these outcomes-- I'll put the answers below the fold.
1. Apartment owners are not allowed to raise the rent on a family living in a unit. Thus, once families secure an apartment, they keep it as long as possible at the same level of rent. Think generations. Incentive to improve the building to satisfy tenants? Little. In fact, insofar that the only way you can get more revenue from your building is by getting new customers, the incentive is to (perhaps actively) make the experience as bad as possible. Rent control, anyone?
2. Building owners don't pay taxes on building until the construction is complete. Thus, buildings in perpetual states of construction don't pay taxes. Not hard to see the incentive there-- keep it unfinished and avoid the State.