Generally speaking, you are looking for tools that will do the work with less effort from you - this leaves you free to concentrate on getting the work done accurately.
Classic case - If you use a Hilti Hammer drill, apart from having huge torque and plenty of weight, you will find it take far less effort to make it drill - you do noy need to force it to work, in fact its much better to let it do its thing. The drill bits will last longer too. They are better ergonomically - you will be able to work longer and harder without suffering the vibration or physical effort.
Now go to a store own brand tool, it may have the same power rating - though pretty unlikely - but not all that power will do useful work, and that’s if they are actually telling the truth. Not only that, it will not be capable of hard work at the upper end of its capacity - it will heat up, and the more it heats up, the less work it will do. It will also take time to cool down.
The casings on good tools will be tough, this does not mean hard - it means they can take impacts and flex slightly rather than crack, the casings will also be more resistant to oils and greases and for real outdoor worksites they will be able to cope with sunlight-which tends to embrittle plastics.
Access to spare parts can be an issue, but these can be very expensive, for example the Dewalt batteries and the trigger speed control module is very expensive indeed, these parts are only just worth the cost of replacement - Batteries have a finite life if the battery drill has heavy use then you can expect to replace it, and perversely lack of use can also damage batteries. I have found that the speed control trigger unit in Dewalt power drills has a tendency to go down, and its never at a convenient time. I would prefer to pay less and have two of them and that way I have a backup instead of having to go back to the shop and dig out a spare.
Makita stuff works well but goes down completely, you just have to realise they are built for a specific lifespan - I would be quite prepared to have a couple of them, rather than just the one DeWalt
Kango stuff just keeps on going, give it all the abuse and it keeps going - testament to this is the secondhand market, used Kango stuff sells for strong money.
Milwaukee, same as Kango
Hilti - best by far, but be prepared to pay for it, can be repaired ad infinitum, but I have never had to do it and although heavy it is less effort to use because it does all the hard stuff whilst all you do is act as the guiding agent.
DeWalt - popular, spares available, but expensive for what it is - good solid case they don’t crack or break. Loads of options available, great for shopfitters if they get the push to drive chucks, you keep your finger on the trigger so it runs all the time, but the chuck disengages the drive until you push it on to the next fastening, which re-engages the drive - superb for doing lots and lots of fast repetitive drilling such as displays and stuff.
Bosch - As far as home users go, its plenty good enough, pretty much semi pro-tools. I find things like clamps and other plastic attachments are not very strong.
Hitachi - General home user, you probably don’t need much more unless you are doing structural work, I would not want to be using it all day though, it would be pretty tiring.
If you are going for static tools, then the construction of the guides and locking mechanisms for the table are all important, they need to be easy to move, must not have a tendency to jam or slide out of alignment, or flex when you put pressure on them. One hand locking levers are best. Don’t go for ones with plastic levers, they are never ever strong or rigid enough Its easy to go for much heavier stuff than you need - get it cut to approximate sizes on the merchant’s machines first - save you lots of money and lots of effort.
Cheap store brands, good for kids to learn on, just noisy toys really.
Skill (actually Skil) lower end??? IMHO they make the best worm drive hand circular saws. They are fantastic. Craftsman power tools need to be lowered down and in no universe are above Skil.