I check mine every 3 days (with my own pressure gauge), I also knock on the tyres and make sure they sound right every day.

I also run my hand round each tyre/ visually inspect them every evening when I get home to see if anything has got stuck in them.

A bit over the top you might say but it has enabled me to find bits of flint , drawing pins, staples, thorns etc before they get worked right in and cause a puncture on a number of occasions.