hiya ken,
Unfortunately,modern electrical devices seem to have a built-in 'user life'.They use components that have MTBF times.
This means 'Mean Time Between Failure'
They achieve this by running 1000's of these parts until they fall out of specification,and can no longer be relied upon to work as expected.
Components with low MTBF's are cheap,and components with high MTBF are VERY expensive.
This is why your 'phone is cheap(er) to make than,say,a piece of hospital equipment,where,if it fails,someone dies.
If you only had to buy your electronic and/or electrical devices once, (because they last forever),then modern manufacturers would go out of bussiness,and the world economy would go down the toilet.
Modern day electronics components are mass produced,and graded for tolerances,and mtbf's.
Lower tolerance parts go for making lower grade goods,where the purchaser doesn't mind,or expect the product to last long,and when it dies,you just go out and buy another.(these are known as grade 1 goods)
Grade 2 goods are,as you would expect,better made,with better quality parts.They last longer,and generally can stand up to more mis-use than grade one goods .
Grade 3 goods are different.If a 'G3' fails,or malfunctions,human life is put at risk.These items must not be allowed to fail,and as a rule,usually have a strict preventative maintenance schedule in place.
Aviation and space exploration ,is quite literally,'on a different planet 'altogether.The limits on tolerances and failures are un-frikkin-believable.
Thank your lucky stars that is was just your 'phone' that failed,and not the on board navigation system of a euro jet fighter,or the engine management system of a car.