Why are wires being laid on the ocean floor?

Question

Iron

Today I watched a documentary, it was mentioned that between many countries, along the seabed, there are wires that provide a cellular network and Internet access.
But why spend so much money on these cables when there are satellite networks?

Answer 1

Satellite communication in comparison with cable has three significant drawbacks:
1) Very long distance to orbit compared to terrestrial / underwater networks, as a result - a large delay between request and response (a few tenths of a second at best, the lower the delay, the lower and more you need satellites))
2) Low bandwidth (for cables - terabits per second, for satellites - an order of magnitude or two lower)
3) Low service life, hence the high cost - in 5-10 years new satellites must be launched.