What is the value of Lr Presets that you can buy?

I've been using Lightroom for 6 months and love it (still getting familiar with Photoshop). There seems to be a lots of free and paid presets one can acquire for Lightroom.I'm trying to understand the value of such presets. All photos that anyone takes will start from a different point on almost every setting in Lr, compared to the assumed starting points of the original creator of a preset. So, to replicate the target look of any preset, I'd have to adjust most sliders anyway. If I knew how to adjust the sliders to reach the target, then why do I need the preset? I don't get it, but I am sure I am missing something. Is it that a multitude of slider settings in a preset are much more likely to be closer to the target look than me almost randomly trying a myriad of combinations? Do professional retouchers buy others presets? via /r/photography http://ift.tt/2fYY1ry