Quote http://en.wikipedia.org/wiki/Flash_memory:

> Mem­o­ry wear

> Anoth­er lim­i­ta­tion is that flash mem­o­ry has a finite num­ber of program-erase cycles (typ­i­cal­ly writ­ten as P/E cycles). Most com­mer­cial­ly avail­able flash prod­ucts are guar­an­teed to with­stand around 100,000 P/E cycles, before the wear begins to dete­ri­o­rate the integri­ty of the storage.[7]

Dudes!!

It’s how the tech­nol­o­gy works