One of four possibilities, in descending order of likelihood

1) They're letting you win for fun / confidence boost / to keep you motivated.

2) You're moving in weird (unsafe) ways (for yourself or them) and they're letting you "win" in order to help you clam down.

3) They're working on something new (not their A game).

4) It's not a strong newaza club / they suck (it happens).

I'm 42 and I let newbies "win" all the time...either because they're being dangerous to themselves, or I'm playing with something new, or trying to see how little I can do to still achieve goal etc.

I think sometimes this gives beginners the wrong idea, so every now and again, I tap them out 5 or 6 times in 4 minutes. Just to remind them that old isn't obsolete :)