Morgan McKinley's survey found that 63% of those who left with less than two years of service cited career progression as the main source of their itch.
Of those with more than two years' service, 70% said the main reason for leaving was the desire for new challenges.
Remuneration, although relatively unimportant for all respondents, was found to become more significant with age: 19% of all those surveyed who were over 30 moved for money, compared with 14% of those under 25.
The survey was based on responses from 136 job seekers, all from investment banks. It confirms what most banks claim they already know: that career structures and stimulation are crucial to staff retention.
Hence positions of responsibility are routinely offered to graduate recruits. JP Morgan, for example, encourages graduates to move between departments, choosing where they want to work.
Damien Carnell, senior consultant at Towers Perrins, says he is unsurprised by the survey's findings. 'Banks are aware of the need for a career structure, but some are finding it hard to achieve. Training and personal development do not always sit well with a highly pressured results-oriented culture,' he says.
Carnell advises that better communication at the banks can help retention. 'People think they should be on a course, but in fact they are learning on the job. This has to be made clear.
'You are learning the most when you are outside your comfort zone. People that are most uncomfortable may well be those that are gaining the most valuable experience.'
And while money may seem unimportant, Carnell argues that there is actually little distinction between remuneration and training.
'Learning and development is important for two things: self esteem and the fact that it will translate into money. In the longer term, training is money.'