Is it a genuine Sony battery or a 3rd-party / eBay part?
I've used both OEM and knockoff batteries and there is a big, big, big difference in how long they are useful for. In my experience, non-OEM batteries are crap after 18 months max. of normal use.
So, you get what you pay for.
Also, if it's been sitting in storage for more than a couple of months, this may also damage it. I've seen this a couple of times - most recently, a battery with 50 cycles that hadn't been used for a year, held only 50% of capacity!
If it's a Sony battery, you could try to "reset" it using some sort of built-in tool (in the Lenovo world it's called "power manager"). This discharges it, recharges it, and then resets the guage.
Regarding planned obsolence, as you may be aware every Li-tech battery (Li-po, Li-ion) is a potential explosive device, that is carefully controlled by it's circuitry. Recent developments in said circuitry / firmware have yielded good results e.g. rapid charging. Also, your Li-ion battery should be good for ~300 cycles before it drops to ~60-70% of max capacity, if you look after it - not 1000 as stated above.