joemaco,
Several posters have pointed out the reasons for thrust adjustments on short final. After landing, most companys' policy is to slow the aircraft down to a controllable taxy speed ASAP which usually means reverse thrust plus moderate braking. The actual amount of braking depends upon the runway condition (wet, dry etc), the runway length and where the turn-offs are, plus as mentioned if ATC ask for a particular exit. The touchdown speed depends on the weather and how heavy the aircraft is, so the same aeroplane might appear to be touching down quite slowly one day into a nice headwind, whereas today has been a nasty, gusty crosswind at my airfield, and I have been watching some very fast arrivals!!!! As a pax it will have felt a bit unpleasant, especially with any small directional corrections the crew make on the runway feeling quite magnified depending upon where you sit in the cabin.
And as an air traffic controller paid to control aircraft landing / departing every day, I can honestly say that Ryanair crews are as professional as any that I control; I can confidently assure you that RYR aircraft land no harder or faster than BA, EZY or any others! (I shall offer no anecdotes of really bad ones that I've witnessed since: 1. I couldn't do any better, and 2. the libel laws in this country....)