Vantaggi
You can wallow in mediocrity and coast along without really effecting any change or process improvements. Most people seem to. Especially in Singapore. If you can land one of the inflated grade roles in London, especially in a back office, zero impact area, like HR, you can live a good life and travel a lot, whilst generating meaningful justification for meaningless projects.
Svantaggi
No management support or strategic direction. Any executive level plan is hampered by middle management agendas and personalities. Some people only looking out for themselves to the detriment of employees. There is evidence of favouring contractors over employees to support personal agendas rather than doing the best for the company. Resulting in lack of progress and increasing cost of (IT) operations.