There is a wine that I know of that carries the descriptor “Reserve” that is made from vines over 100 years old and is fabulous. But for the most part is meaningless, in that someone, at some point reserved it for a wines final blend.
Old is a relative term, if vines are 5 years old, then a 7 year old vine is old!
When a bottle says Shiraz, the local laws might mean a minimum of 85% Shiraz. Heck, Rene Rostaing, the famous Cote Rotie producer, I understand has 100% pure Syrah in two of his top cuvees, 0.5%Viognier in another and up to 4% in his best one.
For me there is only ONE rule, caveat emptor, do your research otherwise you will trip up, I’ve got a few of those T-shirts in my wardrobe.
Names is another one, I just typed Latour into the Wine Advocate search engine and got over 20 responses , ok some were associated Chateau Latour wines and another, a personal favourite of mine Château Latour-Martillac. Latour is a name that can promise delight but also sadly disappointment.
There are a number of clues to a reasonable bottle, without buying it. Does the glass bottle feel cheap? Is the capsule of good quality, rather than some cheap tin or plasticised foil? The label, is the paper of good or better quality? Lots of wire netting and a unique number on a slip of paper by the cork or on the label is easy to produce with todays technology, but no indication of quality.
Years ago, a bottle of Bordeaux with “Superiur” on the label ONLY meant that the wine had an alcohol content 0.5% above the standard, and it didn’t mean that it was anything special, but possibly implied it.
“Specially Selected” is just as disingenuous an expression as “Designer” for clothes or “Architect designed” for a property. Every wine had to be selected for a bottles contents, every piece of clothing ever manufactured must have been designed by someone and show me the property that did not have the hand of some architect before it was erected.
Look beyond, you will make fewer mistakes.