Sharon Osbourne's X Factor hopes were dashed once more when her final act, Alisha came crashing out of the competition following Disco Week.

This is the fourth time Sharon's failed to win the show and while fellow judges Simon Cowell, Louis Walsh and Dannii Minogue all still battling on, Sharon's now expected to watch from the sidelines.

But why? We look at why Sharon's never won the show before...

Poor act choices
Sharon had the first even act to be booted from the show. In 2004, Roberta Howett bowed out after few viewers enjoyed her ethereal folksy voice. Sharon set the standard for forgettable acts from then on. Cassie Compton anyone? Robert Allen?

Too much rock
Sharon's an old rock-chick we know, but the majority of the X Factor audience loves pop. Acts like Ben Mills and Tabby might have had great smoky voices, perfect for big guitar numbers, but the X Factor is all about showstopping ballads and cheesy chart toppers.

Out of her depth
Simon and Louis have worked as pop managers and bosses for years, while it's a field Sharon's new too. Shes used to finding raw talent and exposing it, whereas Simon's used to moulding average voices into the perfect package (Robson and Jermome!). Sharon doesn't seem to know what to do with her artists.

Backstage spats?
If rumours are to be believed Sharon spends more time rowing than helping her acts. Bitter 'rivalries' between Sharon and Dannii have been suggested by the press, and Sharon even walked off the show earlier in the series when her act, Kimberly Southwick was booted in the first live show. Less time stamping her feet and more time with the acts could help...

Bad song choices
Alisha spent most of the series singing songs that were instantly forgettable, like Gabrielle's Dreams, while Kimberley sang It's Raining Men, which was laughably out of her range. Better songs mean more votes.

Bad luck
Even poor Sharon can't be blamed for the departure of Emily Nakanda, who quit the show after happy-slapping revelations.

If Sharon's ever going to win the show that's made her a prime time favourite, she's going to have to buck up her ideas in 2008...

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