This is partly because you're a creature of habit, but also because you sometimes have difficulty recognising the promise in new undertakings.

They had difficulty opening the airtight hatch before the space walk but now the two men were unable to close it.

When you fill in your tax form, you are not allowed to claim three months grace because you have difficulty filling in forms.

These are easy to manage for able-bodied people but could prove a challenge for some older holidaymakers or those who have difficulty walking.