Pencils are awful because if it has been dropped once in its history then the lead inside is cracked into many pieces, and will randomly break off without warning, then you need to sharpen it all the way to the next piece of lead, which then has a fair chance of breaking off almost immediately, and so on until you run out of pencil or patience.
And that's if you have a pencil sharpener handy, which is extra paraphernalia the pencil requires of you. Or else a sharp knife and a steady hand, and then the temptation is always to end up with a blunt tip because at the margin making the point blunter allows you to expose more lead with a minimum of cutting through the wood.
An utterly infuriating instrument. The best writing and drawing instrument is the Mitsubishi Uni-ball Eye UB-150 pen. It always works and it lays down a high-contrast line very smoothly every time. I'm never without one.
The main downside of the UB-150 is that everybody who sees it instantly recognises it and they are liable to grow legs. I recommend buying them in large quantities and sprinkling them all around your house and workplace so that there is such obvious abundance that nobody feels compelled to take one. And if they do, well there are plenty more for everybody else anyway.
As you know for your Uniball, not all pencils are the same. A cheap ball pen can have a lot of problems and stop writting at any moment; a cheap pencil has always a broken core or is impossible to sharpen because the wood turns to pulp. But a decent pencil (Tombow Mono 100 or Faber-Castell 9000 or Staedtler Mars) will get you a perfect core and wood from beginning to end that should not break unless you press like crazy. Despite being excelent, they are cheap, about 2€.
Good quality pencils does no show the cracked lead and if you take good care of them they will not have those cracks. On the other hand you could use a mechanical pencil with replaceable good quality 2mm leads. It can also reuse any little bits of cracked leads laying around. Also if you don't want a blunter point, you can rotate the pencil every few strokes and it would auto-sharp itself.