I got a Jazz about a month ago, used. The owner said it had new plugs about a year ago as part of a service. When I took a look 3 out of 4 were new! Also not quite the right ones; Denso with 0.9mm gap but Honda quote 1.1mm - 1.3mm.
Like.. why go to all the effort needed on these cars to do plugs and only do 3 of them? I guess the garage used what they had in stock and they only had 3. Or they just made a mistake a re-installed one of the originals.
Leads to my second point - This is the most difficult car to do spark plugs on that I've ever owned. Garage might naively quote 15 minutes then when they find it's a 1 hour job decide to make you a kipper. Although, given how popular the Jazz is...
Also you do not need to move the wiper motor out the way, it comes out with / fixed to the metal cowling. Just un-plug it, remove the 5 bolts for the cowling and 1 bolt to the far side with a rubber damper that helps support the wiper motor on the main bulkhead.