here is something i learnt a while ago poles actually wear, from the inside sections scraping the sections, when you telescope them (think about it) answer buy cord and cheap chain from b&q take brush head out use chain to drop through from bottom to thinnest part of pole with cord attached get some old scrim and soak in vaseline and wd40 and pull thru. this will lubricate internal sections thereby reducing friction do it 2 to 3 times per week and you will extend life of poles dramatically.
evidently its the way they used to lubricate gun barrels