Daffodils

I think it’s a mixture of both. Poor soil lacking nutrients will not do the builds any favours, also cheap bulbs do not perform as well as the named ones from nurseries.
I’d dig down where I want them and put some soil improver into the trench. Then in the autumn treat yourself to some new , named ones.

I bought cheap daffodils from Tesco last Autumn. I didn’t get round to planting them until February and they are now in bloom and look lovely so I don’t think it’s Tescos. Daffodils need to be planted at least 4”deep so maybe you haven’t been able to plant deep enough? You could try putting them in. Pot and then digging a hole in the ground to sink them in. If you remove the heads after flowering and leave the leaves for 6 weeks the goodness will go back into the bulbs ready for next Spring.

Giant snowdrops like poor soil.

I would also look at sowing some wildflower seeds , from your area. They will be happy in poor soil, provide you with some later flowers to enjoy and be a haven for the pollinators too.

I buy cheap(er) bulk daffs in places other than garden centres. They do just as well so long as they are planted properly.

Blindness is because they haven't been planted deeply enough.

People often forget that daffs need water after they have flowered to help them build reserves for the next year. As the end of flowering often coincides with a dry spell (like now) don't forget to give them a good soak.

And a bit of a feed