News out if Microsoft Corporation (NASDAQ:MSFT) has revealed that the head of the Windows Phone Marketing team has left the company after just 5 months at the tech giant. Gavin Kim, a note from Microsoft revealed “made a personal decision to leave the company”. The move is one that will rock the boat in the media over the company’s mobile software but it is difficult to guess at the internal machinations at the company. Microsoft, much like other large tech companies, tries to keep an opaque lid on its internal affairs so unless there is a “Why I’m Leaving Microsoft” blog post later today it is difficult to know the circumstances behind the departure.

Kim was famously hired by Microsoft straight out of Samsung late last year. The move was followed by his lead in the marketing campaign “Smoked By Windows Phone” where a Windows running Nokia is measured against Apple and Android’s latest offerings and is shown to beat them on speed and ease of use. That campaign is too early in its run to judge effectiveness yet but leaving after 5 months doesn’t leave us which much to judge Kim on.

The news comes as the Windows Phone platform is embattled by challenges in what was supposed to be the products coming out year. Windows Phone 7.5 and its flagship device the Nokia Lumia 900 have both been well received by critics who say the OS offers something different to Apple Inc. (NASDAQ:AAPL) iOS and Google Inc. (NASDAQ:GOOG) Android software. Though the innovation and quality of the product has been hailed the sales figures have told a different story. Nokia downgraded its projections for sales of its Lumia range from 3.5 million to 2 million for the first quarter earlier this month and several stories have pointed to the under performance of the platform.

The Marketing team at the firm has been left in the control of Eugene Ho who will have a tough job helping launch the product after the rocky start. Microsoft was hoping that an increase in the popularity of its Windows Phone 7.5 would smoothly transition into a good starting position for its Windows Phone 8 software which is due to be launched later this year or early next year. The challenge is there but Microsoft has beaten incumbents before, notably with its Xbox 360, so there is always the chance of upsetting Google’s if not Apple’s success in the smartphone market.