Mezher et al. (2006) conducted a survey of the causes of delays
in the construction industry in Lebanon from the viewpoint of owners,
contractors, and architectural/engineering firms. It was found
that owners had more concerns with regard to financial issues; and
contractors regarded contractual relationships the most important,
whereas consultants considered project management issues to
be the most important causes of delays. Mansfield et al. (1994)
studied the causes of delay and cost overrun in construction projects
in Nigeria. The results showed that the most important causes
are financing and payment for completed works, poor contract
management, changes in site conditions, shortage of material,
and improper planning. Kaming et al. (1997) exploited a questionnaire
survey in Indonesian high-rise construction projects. They
identified 11 variables of delays and seven variables of cost overruns.
Out of this, material cost increased by inflation, inaccurate
quantity take-off, and labor cost increased because of environment
restriction are the first three causes of cost overruns, whereas design
changes, poor labor productivity, inadequate planning, material
shortage, and inaccuracy of material estimate are the first five
causes of delays.