Well I will argue with you over this one.
Old cheap tools ( the ones you get with a motor vehicle ) will usually have some wear on them, particularly the open enders.
However "cheap" tools did not really take a hold till chrome became a must.
To avoid hydrogen embrittlement during plating they had to significantly down grade the alloy that the tools were made from.
This is why I stated to look for unplated tools.
Then following that we went into the "consumer junk" phase because we just all HAD to have that sexy 250 piece of matching spanners that did not fit anything and broke as soon as you put them under stress and then age of meglamaniac corperate retailers began.
If you are going to buy new then go for genuine quality brands.
When I bought the A 65 L I went to Colliers and bought some loose Starwhille ring / open enders. They were not cheap but 30 years latter they are still in perfect nick.
I gave away all of my 1/2 sockets when a mechanic introduced me to quality 3/8 drive sockets so I had to buy some new socket heads and these were Hazets, 12 point ultra thin wall. Have used them with an impact driver and rattle gun, still as good as the day I bought them ( and they are nearly 40 years old ). 12 pointed tools are generally better quality than 6 sided.
In the mid 80's Sidchrome went the way of BSA, downgraded the quality of their product and upped the advertising budget because we were all idiots and would not notice the difference.
It is an arguement I had with the various MD's of Siddons for years. They could have upgraded the steel and become a niche player making the worlds best tools and been a significant exporter but the best they could do was to look at their dicks ( bigger the better ) and went down the mass marketing of rubbish route, swamped the small local market with mediocre tools and lost the home market to equivalent quality imported tools that were 1/2 the price and the trade market to dearer higher quality imported tools.
The difference in price between the best grade of steel and the minimum specification of steel is about double and the cost of the steel is about 3 % of the cost of a spanner so it really should have been a no brainer. The only down side of stronger feed stock is that you loose about 1/10 of the run life from the dies which sounds a lot till you realize that the entire manufacturing represents about 10 % to 15 % of the price you pay ( 30% to 45% ) is the retail mark up, 20% is marketing 5% is warehousing & distribution and the balance is profit.
Any way back to your tool problem.
Quality tools will have clean sharp precise lettering , be thin and seem heavy for their size. Open enders will tapper towards the open end. If they are parrallel then that is the first sign of junk metal . Ring spanners will have a barrel profile around the ring. Again if the ring appears parallel then suspect extra the metal is there to compensate for poor quality steel. Look closely at the set, if the hole appears offset in the spanner then that says "roll forged by a blind man " roll forging produces inferior grain structure to drop forging but is about 1/2 the price.
Look also at the length, unless they are a "stubby" profile be weary of spanners that seem short
Quality tools will have the size stamped into them because after forging they are ground to precise size & then if they pass quality controls get the size & oft the brand name stamped into them. Rubbish tools will have the size raised as it is ground into the die, because as they come out of the die is good enough . Drop forged tools oft will have "drop forged" stamped or forged into the tool. Roll forged tools will have nothing on them and usually have grinding marks along the exterior where the fins have been ground off.
Also look for a country. Dowidats come in 3 grades. Top quality made in Germany , mediocre made in India , junk made in Brazil the latter have no country on them . Gedores are the same except they are made in Germany, India or China. Usually no country = rubbish.
Finally there are the house branded tools. These are made to a price for the retailer . At the best they will be overpriced mediocre tools ( but with very pretty chrome ) and at worst knuckle busters. I avoid them all.