Why does the antenna fail?

Maybe its the device that I was given. But after using it for several months (less than a year), I have been noticing that my Blackberry curve is failing to keep its antenna active. It searches for network in places where it always found network. Did the T-mobile guys reduce the number of towers they supported in London.

Over the span of my use of the blackberry curve, I have noticed that the software can throw some problems at times. For instance, the Gtalk software installed on my Blackberry Curve throws exception errors so frequently that I have stopped using it.

Saying so, I must admit that RIM's devices still lead the pack in terms of business use. They have clearly thought it out. The idea of an e-mail centric mobile phone is just awesome. I remember the last time I spoke with a reporter from FT on smartphones, she said there was broader agreement that Blackberry is the de-facto choice. However, from my experience it seems that there is still some work to be done.