The M4 Sherman tank was a winner by quantity, not by quality. When the US entered World War 2 it did not have a modern tank, even the latest existing designs were obsolete compared to the modern German tanks.
So a new medium tank design was quickly developed, and since it was technically simple and very reliable, a decision was made to immediately start mass producing it in enormous numbers and not wait for the slow development process of an advanced heavy tank. The M26 Pershing heavy tank was slowly developed and reached the war front just before the end of the war.
As a vehicle, the M4 Sherman was very reliable, and as such it was superior to the German tanks, but as a tank the M4 Sherman had several problems, especially when compared to its enemies, the German tanks. It was inferior to them in most aspects. It had a relatively thin armor, an inferior 75mm or 76mm gun which simply could not penetrate the front armor of the German Tiger tanks even from short range, while they could easily destroy the Sherman from long ranges. With such inferiority, mainly in firepower, no wonder the Sherman crews saw the German Tiger tanks as a formidable monster.
In fact, to destroy a German Tiger, the Shermans had to hit it from the side or from behind, and obviously if the Tiger crew saw them approaching, it could destroy some Shermans before the others could eventually destroy it.
But as I wrote, the M4 Sherman was a winner by quantity, so let's check the numbers. The total number of German Tiger and King Tiger tanks produced was 1835, that's all. They were extremely powerful and armored, but also technically unreliable and complex to produce. There were also 4800 German Panther tanks. A majority of these tanks fought against the Russian T-34s in the eastern front. The others were to fight the great majority of the more than 40,000 Sherman tanks produced (a minority fought in the Pacific), and one should remember that the sky above the battlefields were then dominated by swarms of allied fighter-bombers such as the American Thunderbolt and the British Typhoon which excelled in hunting German tanks and kept doing it whenever the sky were clear enough to fly.
I don't have the exact division of tanks to the various war fronts, but if we conservatively assume that 3/4 of the Shermans faced 1/3 of the German tanks (the other tanks went to the Pacific front and to the Russian front respectively), these are the numbers we get, which are not exact, but very clear: 30,000 M4 Shermans versus 600 Tigers and King Tigers and 1500 Panthers.
This is a 14:1 ratio versus the modern German tanks, and a 50:1 ratio versus the formidable Tigers. There were earlier German tanks and powerful tank destroyers, but the Sherman could engage them more easily. It gives a perspective to the immense superiority of the American war industry over its rivals.
If we also consider the strong air support provided by fighter-bombers, [ for example, at the end of the battle of the bulge, British Typhoon fighter-bombers destroyed 175 German tanks in one day, and the larger US Air Force was not on vacation either ], then we must come to the conclusion that although the Sherman tank was inferior to the German tanks, especially the Tigers, it massively outnumbered them, so although combat engagements between Sherman tanks and a German Tiger tank were an unforgettable and terrible experience for the Sherman crews because they usually meant death to one or more Sherman crews, it also meant the death of the greatly outnumbered Tiger's crew. It also meant that such encounters were statistically rare. Most of the time Sherman crews met threats they could more easily deal with and fight them very well.
The M4 Sherman weighed 32 tons, had a crew of five, it had a speed of 29mph and it had fuel for 100 miles. In addition to its 75mm or 76mm main gun it had a typical setting of three machine guns, one in front, one parallel to the main gun, and an anti-aircraft heavy machine gun on top. There were also many variants of the Sherman for every possible role, such as various engineering vehicles. After World War 2 Shermans served in various armies worldwide and even fought in tank battles as late as 1973.