Front door can only be opened from the outside if you have a key. For holidays etc - we have security lock as well - but that is hardly necessary as we have a burglar alarm. We have a side gate, which is normally locked
At the back we have three sets of French doors. This summer they have all been open a lot. and we go about our business in house and garden, without particularly worrying about anyone climbing fences to get in when we are not looking
Although we live in a low crime rural area. Over the years we have had three break-ins and one attempted break-in, we had an attempted break-in in this house 25 years ago, but the alarm went off so they skedaddled with out coming inside.
The other three were in other houses, but apart for some costume jewellry of only sentimental value in the first one , very little has been stolen, as we do not have the kind of high value goods burglars are looking for, no expensive televsions or hifi equipment, no gaming consoles, or desirable computer equipment, no cash or expensive jewellry.
Any way it is only stuff, stuff doesn't matter. On the day our second break in happened the local police arrested a serial childkiller, who had lived in our town and abused local children as well. Somehow, after that, stuff doesn't matter.