Why is it a white elephant? Every service through it, bar Virgin, calls there. Seems pretty well used and successful to me.
Regardless of the semantics of the phrase 'white elephant', it was seen as such because of the lower than expected use. This report sums it up quite nicely;
https://www.gov.uk/government/uploa..._data/file/3932/demand-forecasting-report.pdf
Essentially, at 2008/9, use was 27% lower than expected. Going to backcasting attributes this to the decision to reduce the airport bus link to 3ph rather than originally forecast 6 or 8.
Other stations that weren't used as much as expected include Imperial Wharf, Aylesbury Vale Parkway, Chandlers Ford, Newcraighall and Merryton (page iv).
There was also a number of other papers about the forecasting used for Liverpool South Parkway but I can't find them at the moment. They effectively shifted the blame from Merseytravel not delivering what was promised, to over optimistic demand forecasting.
On a personal level, I enjoyed using South Parkway as my local station. Functional and spacious, but the lack of facilities including a decent cafe, TVMs, toilets and a waiting room nearer the platforms was irritating for such a new station. Not to mention the, err, interesting choice of music that was played, which seemed to be very non-standard late at night