A lot of my favourite games not only have great gameplay but do also have great graphics for the time period and the hardware they were released on. It's funny that everyone is all "gameplay over graphics" when the best games of all time usually had a great presentation. It's not so much graphics as attention to detail. If you've got spooky looking mannequin men in your game that's suggests a few possibilities:
1. You lack the talent to make something that actually looks half-decent.
2. You didn't have the time or budget to make something better.
3. You don't care and just did the bare minimum to get your game out.
The little details are important and they make the great games great. If you can't design an area that looks interesting how can you design an interesting level? How many times in the 16 bit era did I play a game where the dev thought that moving from left to right while jumping an enemies was all it took to make a platformer?
I think it really makes a difference if the developers care about their game. You play some generic EA game and it's just product. No one gives a f*ck. They were just assigned the project by an exec. But when there's real passion on the game design you usually get a real classic. When you care you don't want your game to look like crap.
Though I usually use the publisher's name to spot the shovelware. Lousy graphics help but if I see the THQ logo guess what? That means it's worthless horsesh!t.

And if you can spot the spin-off on your console but not the main series you're probably getting shovelware as well. Has any spin-off like that resulted in anything good?